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  • I want to create a simple function to reset all input values without target input. (Javascript, Jque

    - by question_about_the_problem
    Hi, I want to create a simple function to reset all input values without target input. I don't know how i can do it. Thanks. Here is my sample codes: <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script> function reset_other_inputs(room) { $("input[name^='check_in_date_']").each(function () { if ( $("input[name!='check_in_date_'+room]") ) { this.val(""); } }); $("input[name^='check_out_date_']").each(function () { if ( $("input[name!='check_out_date_'+room]") ) { this.val(""); } }); } </script> <input type="text" name="check_in_date_single" value="single" onClick="reset_other_inputs('single');"> <input type="text" name="check_out_date_single" value="single" onClick="reset_other_inputs('single');"> <input type="text" name="check_in_date_double" value="double" onClick="reset_other_inputs('double');"> <input type="text" name="check_out_date_double" value="double" onClick="reset_other_inputs('double');"> <input type="text" name="check_in_date_triple" value="triple" onClick="reset_other_inputs('triple');"> <input type="text" name="check_out_date_triple" value="triple" onClick="reset_other_inputs('triple');"> <input type="text" name="check_in_date_suite" value="suite" onClick="reset_other_inputs('suite');"> <input type="text" name="check_out_date_suite" value="suite" onClick="reset_other_inputs('suite');">

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  • Call from a singleton class to a function which in turn calls that class's method

    - by dare2be
    Hello, I am still looking for a way to phrase it properly (I'm not a native speaker...). So I have this class SQL which implements the singleton pattern (for obvious reasons) and I also have this function, checkUsr(), which queries the database using one of SQL's methods. Everything works fine as long as I don't call checkUsr() from within the SQL class. When I do so, the scripts just exits and a blank page is displayed - no errors are returned, no exception is thrown... What's happening? And how do I work around this problem? EDIT: class SQL { public static function singleton() { static $instance; if(!isset($instance)) $instance = new SQL; return $instance; } public function tryLoginAuthor( $login, $sha1 ) { (...) } } function checkUsr() { if (!isset($_SESSION['login']) || !isset($_SESSION['sha1'])) throw new Exception('Not logged in', 1); $SQL = SQL::singleton(); $res = $SQL->tryLoginAuthor($_SESSION['login'], $_SESSION['sha1']); if (!isset($res[0])) throw new Exception('Not logged in', 1); }

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  • Strange type-related error

    - by vsb
    I wrote following program: isPrime x = and [x `mod` i /= 0 | i <- [2 .. truncate (sqrt x)]] primes = filter isPrime [1 .. ] it should construct list of prime numbers. But I got this error: [1 of 1] Compiling Main ( 7/main.hs, interpreted ) 7/main.hs:3:16: Ambiguous type variable `a' in the constraints: `Floating a' arising from a use of `isPrime' at 7/main.hs:3:16-22 `RealFrac a' arising from a use of `isPrime' at 7/main.hs:3:16-22 `Integral a' arising from a use of `isPrime' at 7/main.hs:3:16-22 Possible cause: the monomorphism restriction applied to the following: primes :: [a] (bound at 7/main.hs:3:0) Probable fix: give these definition(s) an explicit type signature or use -XNoMonomorphismRestriction Failed, modules loaded: none. If I specify signature for isPrime function explicitly: isPrime :: Integer -> Bool isPrime x = and [x `mod` i /= 0 | i <- [2 .. truncate (sqrt x)]] I can't even compile isPrime function: [1 of 1] Compiling Main ( 7/main.hs, interpreted ) 7/main.hs:2:45: No instance for (RealFrac Integer) arising from a use of `truncate' at 7/main.hs:2:45-61 Possible fix: add an instance declaration for (RealFrac Integer) In the expression: truncate (sqrt x) In the expression: [2 .. truncate (sqrt x)] In a stmt of a list comprehension: i <- [2 .. truncate (sqrt x)] 7/main.hs:2:55: No instance for (Floating Integer) arising from a use of `sqrt' at 7/main.hs:2:55-60 Possible fix: add an instance declaration for (Floating Integer) In the first argument of `truncate', namely `(sqrt x)' In the expression: truncate (sqrt x) In the expression: [2 .. truncate (sqrt x)] Failed, modules loaded: none. Can you help me understand, why am I getting these errors?

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  • Speed of Synchronization vs Normal

    - by Swaranga Sarma
    I have a class which is written for a single thread with no methods being synchronized. class MyClass implements MyInterface{ //interface implementation methods, not synchronized } But we also needed a synchronized version of the class. So we made a wrapper class that implements the same interface but has a constructor that takes an instance of MyClass. Any call to the methods of the synchronized class are delegated to the instance of MyClass. Here is my synchronized class.. class SynchronizedMyClass implements MyInterface{ //the constructor public SynchronizedMyClass(MyInterface i/*this is actually an instance of MyClass*/) //interface implementation methods; all synchronized; all delegated to the MyInterface instance } After all this I ran numerous amounts of test runs with both the classes. The tests involve reading log files and counting URLs in each line. The problem is that the synchronized version of the class is consistently taking less time for the parsing. I am using only one thread for the teste, so there is no chance of deadlocks, race around condition etc etc. Each log file contains more than 5 million lines which means calling the methods more than 5 million times. Can anyone explain why synchronized versiuon of the class migt be taking less time than the normal one?

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  • I can't seem to figure out type variables mixed with classes.

    - by onmach
    I pretty much understand 3/4 the rest of the language, but every time I dip my feet into using classes in a meaningful way in my code I get permantently entrenched. Why doesn't this extremely simple code work? data Room n = Room n n deriving Show class HasArea a where width :: (Num n) => a -> n instance (Num n) => HasArea (Room n) where width (Room w h) = w So, room width is denoted by ints or maybe floats, I don't want to restrict it at this point. Both the class and the instance restrict the n type to Nums, but it still doesn't like it and I get this error: Couldn't match expected type `n1' against inferred type `n' `n1' is a rigid type variable bound by the type signature for `width' at Dungeon.hs:11:16 `n' is a rigid type variable bound by the instance declaration at Dungeon.hs:13:14 In the expression: w In the definition of `width': width (Room w h) = w In the instance declaration for `HasArea (Room n)' So it tells me the types doesn't match, but it doesn't tell me what types it thinks they are, which would be really helpful. As a side note, is there any easy way to debug an error like this? The only way I know to do it is to randomly change stuff until it works.

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  • How to efficiently use LOCK_ESCALATION mssql 2008

    - by Avias
    I'm currently having troubles with frequent deadlocks with a specific user table in MS SQL 2008. Here are some facts about this particular table: Has a large amount of rows (1 to 2 million) All the indexes used on this table only has "use row lock" ticked on its option rows are frequently updated by multiple transactions but are unique (e.g. probably a thousand or more update statements are executed to different unique rows every hour) the table does not use partitions. Upon checking the table on sys.tables, I found that the lock_escalation is set to TABLE I'm very tempted to turn the lock_escalation for this table to DISABLE but I'm not really sure what side effect this would incur. From What I understand, using DISABLE will minimize escalating locks to TABLE level which if combined with the row lock settings of the indexes should theoretically minimize the deadlocks I am encountering.. From what I have read in Determining threshold for lock escalation it seems that locking automatically escalates when a single transaction fetches 5000 rows.. What does a single transaction mean in this sense? A single session/connection getting 5000 rows thru individual update/select statements? Or is it a single sql update/select statement that fetches 5000 or more rows? Any insight is appreciated, btw, n00b DBA here Thanks

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  • Objective C - creating concrete class instances from base class depending upon type

    - by indiantroy
    Just to give a real world example, say the base class is Vehicle and concrete classes are TwoWheeler and FourWheeler. Now the type of the vehicle - TwoWheeler or FourWheeler, is decided by the base class Vehicle. When I create an instance of TwoWheeler/FourWheeler using alloc-init method, it calls the super implementation like below to set the value of common properties defined in the Vehicle class and out of these properties one of them is type that actually decides if the type is TwoWheeler or FourWheeler. if (self = [super initWithDictionary:dict]){ [self setOtherAttributes:dict]; return self; } Now when I get a collection of vehicles some of them could be TwoWheeler and others will be FourWheeler. Hence I cannot directly create an instance of TwoWheeler or FourWheeler like this Vehicle *v = [[TwoWheeler alloc] initWithDictionary:dict]; Is there any way I can create an instance of base class and once I know the type, create an instance of child class depending upon type and return it. With the current implementation, it would result in infinite loop because I call super implementation from concrete class. What would be the perfect design to handle this scenario when I don't know which concrete class should be instantiated beforehand?

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  • How to approach socket programming between C# -> Java (Android)

    - by Alex
    I've recently knocked up a server/client app for Windows & Android that allows one to send a file from Windows to an android phone over a socket connection. It works great for a single file but trying to send multiple files over in a single stream is causing me problems. I've also realised that aside from the binary data, I will need to send messages over the socket to indicate error states and other application messages. I have little experience with network programming and and wondering what is the best way forward. Basically the C# server side of the app just goes into a listening state and uses Socket.SendFile to transmit the file. On Android I use the standard Java Socket.getInputStream() to receive the file. That works great for a single file transfer, but how should I handle multiple files and error/messaging information? Do I need to use a different socket for each file? Should I be using a higher level framework to handle this or can I send everything over the single socket? Any other suggestions for frameworks or learning materials?

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  • Need help INSERT record(s) MySQL DB

    - by JM4
    I have an online form which collects member(s) information and stores it into a very long MySQL database. We allow up to 16 members to enroll at a single time and originally structured the DB to allow such. For example: If 1 Member enrolls, his personal information (first name, last name, address, phone, email) are stored on a single row. If 15 Members enroll (all at once), their personal information are stored in the same single row. The row has information housing columns for all 'possible' inputs. I am trying to consolidate this code and having every nth member that enrolls put onto a new record within the database. I have seen sugestions before for inserting multiple records as such: INSERT INTO tablename VALUES (('$f1name', '$f1address', '$f1phone'), ('$f2name', '$f2address', '$f2phone')... The issue with this is two fold: I do not know how many records are being enrolled from person to person so the only way to make the statement above is to use a loop The information collected from the forms is NOT a single array so I can't loop through one array and have it parse out. My information is collected as individual input fields like such: Member1FirstName, Member1LastName, Member1Phone, Member2Firstname, Member2LastName, Member2Phone... and so on Is it possible to store information in separate rows WITHOUT using a loop (and therefore having to go back and completely restructure my form field names and such (which can't happen due to the way the validation rules are built.)

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  • Oracle Solaris Cluster 4.2 Event and its SNMP Interface

    - by user12609115
    Background The cluster event SNMP interface was first introduced in Oracle Solaris Cluster 3.2 release. The details of the SNMP interface are described in the Oracle Solaris Cluster System Administration Guide and the Cluster 3.2 SNMP blog. Prior to the Oracle Solaris Cluster 4.2 release, when the event SNMP interface was enabled, it would take effect on WARNING or higher severity events. The events with WARNING or higher severity are usually for the status change of a cluster component from ONLINE to OFFLINE. The interface worked like an alert/alarm interface when some components in the cluster were out of service (changed to OFFLINE). The consumers of this interface could not get notification for all status changes and configuration changes in the cluster. Cluster Event and its SNMP Interface in Oracle Solaris Cluster 4.2 The user model of the cluster event SNMP interface is the same as what was provided in the previous releases. The cluster event SNMP interface is not enabled by default on a freshly installed cluster; you can enable it by using the cluster event SNMP administration commands on any cluster nodes. Usually, you only need to enable it on one of the cluster nodes or a subset of the cluster nodes because all cluster nodes get the same cluster events. When it is enabled, it is responsible for two basic tasks. • Logs up to 100 most recent NOTICE or higher severity events to the MIB. • Sends SNMP traps to the hosts that are configured to receive the above events. The changes in the Oracle Solaris Cluster 4.2 release are1) Introduction of the NOTICE severity for the cluster configuration and status change events.The NOTICE severity is introduced for the cluster event in the 4.2 release. It is the severity between the INFO and WARNING severity. Now all severities for the cluster events are (from low to high) • INFO (not exposed to the SNMP interface) • NOTICE (newly introduced in the 4.2 release) • WARNING • ERROR • CRITICAL • FATAL In the 4.2 release, the cluster event system is enhanced to make sure at least one event with the NOTICE or a higher severity will be generated when there is a configuration or status change from a cluster component instance. In other words, the cluster events from a cluster with the NOTICE or higher severities will cover all status and configuration changes in the cluster (include all component instances). The cluster component instance here refers to an instance of the following cluster componentsnode, quorum, resource group, resource, network interface, device group, disk, zone cluster and geo cluster heartbeat. For example, pnode1 is an instance of the cluster node component, and oracleRG is an instance of the cluster resource group. With the introduction of the NOTICE severity event, when the cluster event SNMP interface is enabled, the consumers of the SNMP interface will get notification for all status and configuration changes in the cluster. A thrid-party system management platform with the cluster SNMP interface integration can generate alarms and clear alarms programmatically, because it can get notifications for the status change from ONLINE to OFFLINE and also from OFFLINE to ONLINE. 2) Customization for the cluster event SNMP interface • The number of events logged to the MIB is 100. When the number of events stored in the MIB reaches 100 and a new qualified event arrives, the oldest event will be removed before storing the new event to the MIB (FIFO, first in, first out). The 100 is the default and minimum value for the number of events stored in the MIB. It can be changed by setting the log_number property value using the clsnmpmib command. The maximum number that can be set for the property is 500. • The cluster event SNMP interface takes effect on the NOTICE or high severity events. The NOTICE severity is also the default and lowest event severity for the SNMP interface. The SNMP interface can be configured to take effect on other higher severity events, such as WARNING or higher severity events by setting the min_severity property to the WARNING. When the min_severity property is set to the WARNING, the cluster event SNMP interface would behave the same as the previous releases (prior to the 4.2 release). Examples, • Set the number of events stored in the MIB to 200 # clsnmpmib set -p log_number=200 event • Set the interface to take effect on WARNING or higher severity events. # clsnmpmib set -p min_severity=WARNING event Administering the Cluster Event SNMP Interface Oracle Solaris Cluster provides the following three commands to administer the SNMP interface. • clsnmpmib: administer the SNMP interface, and the MIB configuration. • clsnmphost: administer hosts for the SNMP traps • clsnmpuser: administer SNMP users (specific for SNMP v3 protocol) Only clsnmpmib is changed in the 4.2 release to support the aforementioned customization of the SNMP interface. Here are some simple examples using the commands. Examples: 1. Enable the cluster event SNMP interface on the local node # clsnmpmib enable event 2. Display the status of the cluster event SNMP interface on the local node # clsnmpmib show -v 3. Configure my_host to receive the cluster event SNMP traps. # clsnmphost add my_host Cluster Event SNMP Interface uses the common agent container SNMP adaptor, which is based on the JDMK SNMP implementation as its SNMP agent infrastructure. By default, the port number for the SNMP MIB is 11161, and the port number for the SNMP traps is 11162. The port numbers can be changed by using the cacaoadm. For example, # cacaoadm list-params Print all changeable parameters. The output includes the snmp-adaptor-port and snmp-adaptor-trap-port properties. # cacaoadm set-param snmp-adaptor-port=1161 Set the SNMP MIB port number to 1161. # cacaoadm set-param snmp-adaptor-trap-port=1162 Set the SNMP trap port number to 1162. The cluster event SNMP MIB is defined in sun-cluster-event-mib.mib, which is located in the /usr/cluster/lib/mibdirectory. Its OID is 1.3.6.1.4.1.42.2.80, that can be used to walk through the MIB data. Again, for more detail information about the cluster event SNMP interface, please see the Oracle Solaris Cluster 4.2 System Administration Guide. - Leland Chen 

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  • Is Berkeley DB a NoSQL solution?

    - by Gregory Burd
    Berkeley DB is a library. To use it to store data you must link the library into your application. You can use most programming languages to access the API, the calls across these APIs generally mimic the Berkeley DB C-API which makes perfect sense because Berkeley DB is written in C. The inspiration for Berkeley DB was the DBM library, a part of the earliest versions of UNIX written by AT&T's Ken Thompson in 1979. DBM was a simple key/value hashtable-based storage library. In the early 1990s as BSD UNIX was transitioning from version 4.3 to 4.4 and retrofitting commercial code owned by AT&T with unencumbered code, it was the future founders of Sleepycat Software who wrote libdb (aka Berkeley DB) as the replacement for DBM. The problem it addressed was fast, reliable local key/value storage. At that time databases almost always lived on a single node, even the most sophisticated databases only had simple fail-over two node solutions. If you had a lot of data to store you would choose between the few commercial RDBMS solutions or to write your own custom solution. Berkeley DB took the headache out of the custom approach. These basic market forces inspired other DBM implementations. There was the "New DBM" (ndbm) and the "GNU DBM" (GDBM) and a few others, but the theme was the same. Even today TokyoCabinet calls itself "a modern implementation of DBM" mimicking, and improving on, something first created over thirty years ago. In the mid-1990s, DBM was the name for what you needed if you were looking for fast, reliable local storage. Fast forward to today. What's changed? Systems are connected over fast, very reliable networks. Disks are cheep, fast, and capable of storing huge amounts of data. CPUs continued to follow Moore's Law, processing power that filled a room in 1990 now fits in your pocket. PCs, servers, and other computers proliferated both in business and the personal markets. In addition to the new hardware entire markets, social systems, and new modes of interpersonal communication moved onto the web and started evolving rapidly. These changes cause a massive explosion of data and a need to analyze and understand that data. Taken together this resulted in an entirely different landscape for database storage, new solutions were needed. A number of novel solutions stepped up and eventually a category called NoSQL emerged. The new market forces inspired the CAP theorem and the heated debate of BASE vs. ACID. But in essence this was simply the market looking at what to trade off to meet these new demands. These new database systems shared many qualities in common. There were designed to address massive amounts of data, millions of requests per second, and scale out across multiple systems. The first large-scale and successful solution was Dynamo, Amazon's distributed key/value database. Dynamo essentially took the next logical step and added a twist. Dynamo was to be the database of record, it would be distributed, data would be partitioned across many nodes, and it would tolerate failure by avoiding single points of failure. Amazon did this because they recognized that the majority of the dynamic content they provided to customers visiting their web store front didn't require the services of an RDBMS. The queries were simple, key/value look-ups or simple range queries with only a few queries that required more complex joins. They set about to use relational technology only in places where it was the best solution for the task, places like accounting and order fulfillment, but not in the myriad of other situations. The success of Dynamo, and it's design, inspired the next generation of Non-SQL, distributed database solutions including Cassandra, Riak and Voldemort. The problem their designers set out to solve was, "reliability at massive scale" so the first focal point was distributed database algorithms. Underneath Dynamo there is a local transactional database; either Berkeley DB, Berkeley DB Java Edition, MySQL or an in-memory key/value data structure. Dynamo was an evolution of local key/value storage onto networks. Cassandra, Riak, and Voldemort all faced similar design decisions and one, Voldemort, choose Berkeley DB Java Edition for it's node-local storage. Riak at first was entirely in-memory, but has recently added write-once, append-only log-based on-disk storage similar type of storage as Berkeley DB except that it is based on a hash table which must reside entirely in-memory rather than a btree which can live in-memory or on disk. Berkeley DB evolved too, we added high availability (HA) and a replication manager that makes it easy to setup replica groups. Berkeley DB's replication doesn't partitioned the data, every node keeps an entire copy of the database. For consistency, there is a single node where writes are committed first - a master - then those changes are delivered to the replica nodes as log records. Applications can choose to wait until all nodes are consistent, or fire and forget allowing Berkeley DB to eventually become consistent. Berkeley DB's HA scales-out quite well for read-intensive applications and also effectively eliminates the central point of failure by allowing replica nodes to be elected (using a PAXOS algorithm) to mastership if the master should fail. This implementation covers a wide variety of use cases. MemcacheDB is a server that implements the Memcache network protocol but uses Berkeley DB for storage and HA to replicate the cache state across all the nodes in the cache group. Google Accounts, the user authentication layer for all Google properties, was until recently running Berkeley DB HA. That scaled to a globally distributed system. That said, most NoSQL solutions try to partition (shard) data across nodes in the replication group and some allow writes as well as reads at any node, Berkeley DB HA does not. So, is Berkeley DB a "NoSQL" solution? Not really, but it certainly is a component of many of the existing NoSQL solutions out there. Forgetting all the noise about how NoSQL solutions are complex distributed databases when you boil them down to a single node you still have to store the data to some form of stable local storage. DBMs solved that problem a long time ago. NoSQL has more to do with the layers on top of the DBM; the distributed, sometimes-consistent, partitioned, scale-out storage that manage key/value or document sets and generally have some form of simple HTTP/REST-style network API. Does Berkeley DB do that? Not really. Is Berkeley DB a "NoSQL" solution today? Nope, but it's the most robust solution on which to build such a system. Re-inventing the node-local data storage isn't easy. A lot of people are starting to come to appreciate the sophisticated features found in Berkeley DB, even mimic them in some cases. Could Berkeley DB grow into a NoSQL solution? Absolutely. Our key/value API could be extended over the net using any of a number of existing network protocols such as memcache or HTTP/REST. We could adapt our node-local data partitioning out over replicated nodes. We even have a nice query language and cost-based query optimizer in our BDB XML product that we could reuse were we to build out a document-based NoSQL-style product. XML and JSON are not so different that we couldn't adapt one to work with the other interchangeably. Without too much effort we could add what's missing, we could jump into this No SQL market withing a single product development cycle. Why isn't Berkeley DB already a NoSQL solution? Why aren't we working on it? Why indeed...

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  • Using Table-Valued Parameters in SQL Server

    - by Jesse
    I work with stored procedures in SQL Server pretty frequently and have often found myself with a need to pass in a list of values at run-time. Quite often this list contains a set of ids on which the stored procedure needs to operate the size and contents of which are not known at design time. In the past I’ve taken the collection of ids (which are usually integers), converted them to a string representation where each value is separated by a comma and passed that string into a VARCHAR parameter of a stored procedure. The body of the stored procedure would then need to parse that string into a table variable which could be easily consumed with set-based logic within the rest of the stored procedure. This approach works pretty well but the VARCHAR variable has always felt like an un-wanted “middle man” in this scenario. Of course, I could use a BULK INSERT operation to load the list of ids into a temporary table that the stored procedure could use, but that approach seems heavy-handed in situations where the list of values is usually going to contain only a few dozen values. Fortunately SQL Server 2008 introduced the concept of table-valued parameters which effectively eliminates the need for the clumsy middle man VARCHAR parameter. Example: Customer Transaction Summary Report Let’s say we have a report that can summarize the the transactions that we’ve conducted with customers over a period of time. The report returns a pretty simple dataset containing one row per customer with some key metrics about how much business that customer has conducted over the date range for which the report is being run. Sometimes the report is run for a single customer, sometimes it’s run for all customers, and sometimes it’s run for a handful of customers (i.e. a salesman runs it for the customers that fall into his sales territory). This report can be invoked from a website on-demand, or it can be scheduled for periodic delivery to certain users via SQL Server Reporting Services. Because the report can be created from different places and the query to generate the report is complex it’s been packed into a stored procedure that accepts three parameters: @startDate – The beginning of the date range for which the report should be run. @endDate – The end of the date range for which the report should be run. @customerIds – The customer Ids for which the report should be run. Obviously, the @startDate and @endDate parameters are DATETIME variables. The @customerIds parameter, however, needs to contain a list of the identity values (primary key) from the Customers table representing the customers that were selected for this particular run of the report. In prior versions of SQL Server we might have made this parameter a VARCHAR variable, but with SQL Server 2008 we can make it into a table-valued parameter. Defining And Using The Table Type In order to use a table-valued parameter, we first need to tell SQL Server about what the table will look like. We do this by creating a user defined type. For the purposes of this stored procedure we need a very simple type to model a table variable with a single integer column. We can create a generic type called ‘IntegerListTableType’ like this: CREATE TYPE IntegerListTableType AS TABLE (Value INT NOT NULL) Once defined, we can use this new type to define the @customerIds parameter in the signature of our stored procedure. The parameter list for the stored procedure definition might look like: 1: CREATE PROCEDURE dbo.rpt_CustomerTransactionSummary 2: @starDate datetime, 3: @endDate datetime, 4: @customerIds IntegerListTableTableType READONLY   Note the ‘READONLY’ statement following the declaration of the @customerIds parameter. SQL Server requires any table-valued parameter be marked as ‘READONLY’ and no DML (INSERT/UPDATE/DELETE) statements can be performed on a table-valued parameter within the routine in which it’s used. Aside from the DML restriction, however, you can do pretty much anything with a table-valued parameter as you could with a normal TABLE variable. With the user defined type and stored procedure defined as above, we could invoke like this: 1: DECLARE @cusomterIdList IntegerListTableType 2: INSERT @customerIdList VALUES (1) 3: INSERT @customerIdList VALUES (2) 4: INSERT @customerIdList VALUES (3) 5:  6: EXEC dbo.rpt_CustomerTransationSummary 7: @startDate = '2012-05-01', 8: @endDate = '2012-06-01' 9: @customerIds = @customerIdList   Note that we can simply declare a variable of type ‘IntegerListTableType’ just like any other normal variable and insert values into it just like a TABLE variable. We could also populate the variable with a SELECT … INTO or INSERT … SELECT statement if desired. Using The Table-Valued Parameter With ADO .NET Invoking a stored procedure with a table-valued parameter from ADO .NET is as simple as building a DataTable and passing it in as the Value of a SqlParameter. Here’s some example code for how we would construct the SqlParameter for the @customerIds parameter in our stored procedure: 1: var customerIdsParameter = new SqlParameter(); 2: customerIdParameter.Direction = ParameterDirection.Input; 3: customerIdParameter.TypeName = "IntegerListTableType"; 4: customerIdParameter.Value = selectedCustomerIds.ToIntegerListDataTable("Value");   All we’re doing here is new’ing up an instance of SqlParameter, setting the pamameters direction, specifying the name of the User Defined Type that this parameter uses, and setting its value. We’re assuming here that we have an IEnumerable<int> variable called ‘selectedCustomerIds’ containing all of the customer Ids for which the report should be run. The ‘ToIntegerListDataTable’ method is an extension method of the IEnumerable<int> type that looks like this: 1: public static DataTable ToIntegerListDataTable(this IEnumerable<int> intValues, string columnName) 2: { 3: var intergerListDataTable = new DataTable(); 4: intergerListDataTable.Columns.Add(columnName); 5: foreach(var intValue in intValues) 6: { 7: var nextRow = intergerListDataTable.NewRow(); 8: nextRow[columnName] = intValue; 9: intergerListDataTable.Rows.Add(nextRow); 10: } 11:  12: return intergerListDataTable; 13: }   Since the ‘IntegerListTableType’ has a single int column called ‘Value’, we pass that in for the ‘columnName’ parameter to the extension method. The method creates a new single-columned DataTable using the provided column name then iterates over the items in the IEnumerable<int> instance adding one row for each value. We can then use this SqlParameter instance when invoking the stored procedure just like we would use any other parameter. Advanced Functionality Using passing a list of integers into a stored procedure is a very simple usage scenario for the table-valued parameters feature, but I’ve found that it covers the majority of situations where I’ve needed to pass a collection of data for use in a query at run-time. I should note that BULK INSERT feature still makes sense for passing large amounts of data to SQL Server for processing. MSDN seems to suggest that 1000 rows of data is the tipping point where the overhead of a BULK INSERT operation can pay dividends. I should also note here that table-valued parameters can be used to deal with more complex data structures than single-columned tables of integers. A User Defined Type that backs a table-valued parameter can use things like identities and computed columns. That said, using some of these more advanced features might require the use the SqlDataRecord and SqlMetaData classes instead of a simple DataTable. Erland Sommarskog has a great article on his website that describes when and how to use these classes for table-valued parameters. What About Reporting Services? Earlier in the post I referenced the fact that our example stored procedure would be called from both a web application and a SQL Server Reporting Services report. Unfortunately, using table-valued parameters from SSRS reports can be a bit tricky and warrants its own blog post which I’ll be putting together and posting sometime in the near future.

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  • New OFM versions released SOA Suite 11.1.1.4 &amp; BPM 11.1.1.4 &amp; JDeveloper 11.1.1.4 WebLogic on JRockit 10.3.4 feedback from the community

    - by Jürgen Kress
    Oracle SOA Suite 11g Installations This is the latest release of the Oracle SOA Suite 11g. Please see the Documentation tab for Release Notes, Installation Guides and other release specific information. Please also see the List of New Features and Samples provided for this release. Release 11gR1 (11.1.1.4.0) Microsoft Windows (32-bit JVM) Linux (32-bit JVM) Generic Oracle JDeveloper 11g Rel 1 (11.1.1.x) (JDeveloper + ADF) Integrated development environment certified on Windows, Linux, and Macintosh. License is free (read the Pricing FAQ). Studio Edition for Windows (1.2 GB) | Studio Edition for Linux (1.3 GB) | See All See Additional Development Tools Oracle WebLogic Server 11g Rel 1 (10.3.4) Installers The WebLogic Server installers include Oracle Coherence and Oracle Enterprise Pack for Eclipse and supports development with other Fusion Middleware products . The zip includes WebLogic Server only and is intended for WebLogic Server development only. Linux x86 (1.1 GB) | Windows x86 (1 GB) Zip for Windows x86, Linux x86, Mac OS X (316 MB) | See All Oracle WebLogic Server 11gR1 (10.3.4) on JRockit Virtual Edition Download For additional downloads please visit the Oracle Fusion Middleware Products Update Center Share your feedback with the @soacommunity on twitter SOASimone Simone Geib SOA Suite 11gR1 (11.1.1.4.0) has just been released: http://www.oracle.com/technetwork/middleware/soasuite/downloads/index.html gschmutz gschmutz My new blog post: WebLogic Server, JDev, SOA, BPM, OSB and CEP 11.1.1.4 (PS3) available! - http://tinyurl.com/4negnpn simon_haslam Simon Haslam I'm very pleased to see WLS 10.3.4 for JRockit VE launched at the same time as the rest of PS3 http://j.mp/gl1nQm (32bit anyway) lucasjellema Lucas Jellema See http://www.oracle.com/ocom/groups/public/@otn/documents/webcontent/156082.xml for PS3 extension downloads BPM, SOA Editor, WebCenter demed demed List of new features in @OracleSOA 11gR1 PS3: http://bit.ly/fVRwsP is not extremely long but huge release by # of bugs fixed. Go! biemond Edwin Biemond WebLogic 10.3.4 new features http://bit.ly/f7L1Eu Exalogic Elastic Cloud , JPA2 , Maven plugin, OWSM policies on WebLogic SCA applications JDeveloper JDeveloper & ADF JDeveloper and Oracle ADF 11g Release 1 Patch Set 3 (11.1.1.4.0): New Features and Bug Fixes http://bit.ly/feghnY simon_haslam Simon Haslam WebLogic Server 10.3.4 (i.e. 11gR1 PS3) available now too http://bit.ly/eeysZ2 JDeveloper JDeveloper & ADF Share your impressions on the new JDeveloper 11g Patchset 3 release that came out today! Download it here: http://bit.ly/dogRN8 VikasAatOracle Vikas Anand SOA Suite 11gR1PS3 is Hotpluggable ...see list of features that @Demed posted..#soa #soacommunity   New versions of Oracle Fusion Middleware 11g R1 (11.1.1.4.x)  include: Oracle WebLogic Server 11g R1 (10.3.4) Oracle SOA Suite 11g R1 (11.1.1.4.0) Oracle Business Process Management 11g R1 (11.1.1.4.0) Oracle Complex Event Processing 11g R1 (11.1.1.4.0) Oracle Application Integration Architecture Foundation Pack 11g R1 (11.1.1.4.0) Oracle Service Bus 11g R1 (11.1.1.4.0) Oracle Enterprise Repository 11g R1 (11.1.1.4.0) Oracle Identity Management 11g R1 (11.1.1.4.0) Oracle Enterprise Content Management 11g R1 (11.1.1.4.0) Oracle WebCenter 11g R1 (11.1.1.4.0) - coming soon Oracle Forms, Reports, Portal & Discoverer 11g R1 (11.1.1.4.0) Oracle Repository Creation Utility 11g R1 (11.1.1.4.0) Oracle JDeveloper & Application Development Runtime 11g R1 (11.1.1.4.0) Resources Download  (OTN) Certification Documentation   New Features in Oracle SOA Suite 11g Release 1 (11.1.1.4.0) Updated: January, 2011 Go to Oracle SOA Suite 11g Doc Introduction Oracle SOA Suite 11gR1 (11.1.1.4.0) includes both bug fixes as well as new features listed below - click on the title of each feature for more details. Downloads, documentation links and more information on the Oracle SOA Suite available on the SOA Suite OTN page and as always, we welcome your feedback on the SOA OTN forum. New in Oracle SOA Suite in this release BPEL Component BPEL 2.0 support in JDeveloper The BPEL editor in JDeveloper now generates BPEL 2.0 code and introduces several new activities. Augmented XML variables auto-initialization capabilities The XML variable auto-initialization capabilities have been enhanced to support two need additional use cases: to initialize the to-spec node if it doesn't exist during the rule and to initialize array elements. New Assign Activity dialog The new Assign Activity supports the same drag & drop paradigm used for the XSLT mapper, greatly streamlining the task of assigning multiple variables. Mediator Component Time window parameter for the resequencer This new parameter lets users initiate a best-effort resequencing based on a time window rather than a number of messages. Support for attachments in the Mediator assign dialog The Mediator assign dialog now supports attachment, enabling usage of the Mediator to transmit attachments even if source and target schemas are different. Adapters & Bindings ChunkSize property added to the File Adapter header properties The ChunkSize property of the File Adapter is now available as a header property, allowing in-process modification of the value for this property. Improved support for distributed WLS JMS topics though automatic rebalancing of listeners The JMS Adapter has been enhanced to subscribe to administrative events from WLS JMS. Based on these events, it dynamically rebalances listeners when there are changes to the members of a local or remote WLS JMS distributed destination. JDeveloper configuration wizard for custom JCA adapters A new wizard is available in JDeveloper to configure custom-built adapters Administration & Enterprise Manager Enhanced purging capabilities to manage database growth Historical instance data can now be purged using three different strategies: batch script, scheduled batch script or data partitioning. Asynchronous bulk instance deletion in Enterprise Manager Bulk deletion of instances in Enterprise Manager now executes as an asynchronous operation in Enterprise Manager, returning control to the user as soon as the action has been submitted and acknowledged. B2B Ability to schedule partner downtime This feature allows trading partners to notify each other about planned downtime and to delay delivery of messages during that period. Message sequencing B2B now supports both inbound and outbound message sequencing. Simplified BAM integration with B2B B2B ships with various pre-configured artifacts to simplify monitoring in BAM. Instance Message Java API for B2B The new instance message Java API supports programmatic access to B2B instance message data. Oracle Service Bus (OSB) Certification of the File and FTP JCA Adapters The File and FTP JCA adapters are now certified for use with Oracle Service Bus (in addition to the native transports). Security enhancements Oracle Service Bus now supports SAML 2.0 as well as the OWSM authorization policies. Check the Oracle Service Bus 11.1.1.4 Release Notes for a complete list of new features. Installation, Hot-Pluggability & Certifications Ability to run Oracle SOA Suite on IBM WebSphere Application Server Oracle SOA Suite can now be deployed on IBM WebSphere Application Server Network Deployment (ND) 7.0.11 and IBM WebSphere Application Server 7.0.11. Single JVM developer installation template Oracle SOA Suite can now be targeted to the WebLogic admin server - there is no requirement to also have a managed server. This topology is intended to minimize the memory foorprint of development environments. This is in addition to the list of supported browsers, operating systems and databases already certified in prior releases. Complex Event Processing (CEP) IDE enhancements This release introduces several enhancements to the development IDE, such as adapter wizards and event-type repository. CQL enhancements CQL enhancements include JDBC data cartridges and parametrized queries. Tracing and injecting events in the Event Processing Network (EPN) In the development environment you can now trace and inject events. Check the Oracle CEP 11.1.1.4 Release Notes for a complete list of new features. SOA Suite page on OTN For more information on SOA Specialization and the SOA Partner Community please feel free to register at www.oracle.com/goto/emea/soa (OPN account required) Blog Twitter LinkedIn Mix Forum Wiki Website Technorati Tags: SOA Suite 11.1.1.4,JDeveloper 11.1.1.4,WebLogic 10.3.4,JRockit 10.3.4,SOA Community,Oracle,OPN,SOA,Simone Geib,Guido Schmutz,Edwin Biemond,Lucas Jellema,Simon Haslam,Demed,Vikas Anand,Jürgen Kress

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  • General monitoring for SQL Server Analysis Services using Performance Monitor

    - by Testas
    A recent customer engagement required a setup of a monitoring solution for SSAS, due to the time restrictions placed upon this, native Windows Performance Monitor (Perfmon) and SQL Server Profiler Monitoring Tools was used as using a third party tool would have meant the customer providing an additional monitoring server that was not available.I wanted to outline the performance monitoring counters that was used to monitor the system on which SSAS was running. Due to the slow query performance that was occurring during certain scenarios, perfmon was used to establish if any pressure was being placed on the Disk, CPU or Memory subsystem when concurrent connections access the same query, and Profiler to pinpoint how the query was being managed within SSAS, profiler I will leave for another blogThis guide is not designed to provide a definitive list of what should be used when monitoring SSAS, different situations may require the addition or removal of counters as presented by the situation. However I hope that it serves as a good basis for starting your monitoring of SSAS. I would also like to acknowledge Chris Webb’s awesome chapters from “Expert Cube Development” that also helped shape my monitoring strategy:http://cwebbbi.spaces.live.com/blog/cns!7B84B0F2C239489A!6657.entrySimulating ConnectionsTo simulate the additional connections to the SSAS server whilst monitoring, I used ascmd to simulate multiple connections to the typical and worse performing queries that were identified by the customer. A similar sript can be downloaded from codeplex at http://www.codeplex.com/SQLSrvAnalysisSrvcs.     File name: ASCMD_StressTestingScripts.zip. Performance MonitorWithin performance monitor,  a counter log was created that contained the list of counters below. The important point to note when running the counter log is that the RUN AS property within the counter log properties should be changed to an account that has rights to the SSAS instance when monitoring MSAS counters. Failure to do so means that the counter log runs under the system account, no errors or warning are given while running the counter log, and it is not until you need to view the MSAS counters that they will not be displayed if run under the default account that has no right to SSAS. If your connection simulation takes hours, this could prove quite frustrating if not done beforehand JThe counters used……  Object Counter Instance Justification System Processor Queue legnth N/A Indicates how many threads are waiting for execution against the processor. If this counter is consistently higher than around 5 when processor utilization approaches 100%, then this is a good indication that there is more work (active threads) available (ready for execution) than the machine's processors are able to handle. System Context Switches/sec N/A Measures how frequently the processor has to switch from user- to kernel-mode to handle a request from a thread running in user mode. The heavier the workload running on your machine, the higher this counter will generally be, but over long term the value of this counter should remain fairly constant. If this counter suddenly starts increasing however, it may be an indicating of a malfunctioning device, especially if the Processor\Interrupts/sec\(_Total) counter on your machine shows a similar unexplained increase Process % Processor Time sqlservr Definately should be used if Processor\% Processor Time\(_Total) is maxing at 100% to assess the effect of the SQL Server process on the processor Process % Processor Time msmdsrv Definately should be used if Processor\% Processor Time\(_Total) is maxing at 100% to assess the effect of the SQL Server process on the processor Process Working Set sqlservr If the Memory\Available bytes counter is decreaing this counter can be run to indicate if the process is consuming larger and larger amounts of RAM. Process(instance)\Working Set measures the size of the working set for each process, which indicates the number of allocated pages the process can address without generating a page fault. Process Working Set msmdsrv If the Memory\Available bytes counter is decreaing this counter can be run to indicate if the process is consuming larger and larger amounts of RAM. Process(instance)\Working Set measures the size of the working set for each process, which indicates the number of allocated pages the process can address without generating a page fault. Processor % Processor Time _Total and individual cores measures the total utilization of your processor by all running processes. If multi-proc then be mindful only an average is provided Processor % Privileged Time _Total To see how the OS is handling basic IO requests. If kernel mode utilization is high, your machine is likely underpowered as it's too busy handling basic OS housekeeping functions to be able to effectively run other applications. Processor % User Time _Total To see how the applications is interacting from a processor perspective, a high percentage utilisation determine that the server is dealing with too many apps and may require increasing thje hardware or scaling out Processor Interrupts/sec _Total  The average rate, in incidents per second, at which the processor received and serviced hardware interrupts. Shoulr be consistant over time but a sudden unexplained increase could indicate a device malfunction which can be confirmed using the System\Context Switches/sec counter Memory Pages/sec N/A Indicates the rate at which pages are read from or written to disk to resolve hard page faults. This counter is a primary indicator of the kinds of faults that cause system-wide delays, this is the primary counter to watch for indication of possible insufficient RAM to meet your server's needs. A good idea here is to configure a perfmon alert that triggers when the number of pages per second exceeds 50 per paging disk on your system. May also want to see the configuration of the page file on the Server Memory Available Mbytes N/A is the amount of physical memory, in bytes, available to processes running on the computer. if this counter is greater than 10% of the actual RAM in your machine then you probably have more than enough RAM. monitor it regularly to see if any downward trend develops, and set an alert to trigger if it drops below 2% of the installed RAM. Physical Disk Disk Transfers/sec for each physical disk If it goes above 10 disk I/Os per second then you've got poor response time for your disk. Physical Disk Idle Time _total If Disk Transfers/sec is above  25 disk I/Os per second use this counter. which measures the percent time that your hard disk is idle during the measurement interval, and if you see this counter fall below 20% then you've likely got read/write requests queuing up for your disk which is unable to service these requests in a timely fashion. Physical Disk Disk queue legnth For the OLAP and SQL physical disk A value that is consistently less than 2 means that the disk system is handling the IO requests against the physical disk Network Interface Bytes Total/sec For the NIC Should be monitored over a period of time to see if there is anb increase/decrease in network utilisation Network Interface Current Bandwidth For the NIC is an estimate of the current bandwidth of the network interface in bits per second (BPS). MSAS 2005: Memory Memory Limit High KB N/A Shows (as a percentage) the high memory limit configured for SSAS in C:\Program Files\Microsoft SQL Server\MSAS10.MSSQLSERVER\OLAP\Config\msmdsrv.ini MSAS 2005: Memory Memory Limit Low KB N/A Shows (as a percentage) the low memory limit configured for SSAS in C:\Program Files\Microsoft SQL Server\MSAS10.MSSQLSERVER\OLAP\Config\msmdsrv.ini MSAS 2005: Memory Memory Usage KB N/A Displays the memory usage of the server process. MSAS 2005: Memory File Store KB N/A Displays the amount of memory that is reserved for the Cache. Note if total memory limit in the msmdsrv.ini is set to 0, no memory is reserved for the cache MSAS 2005: Storage Engine Query Queries from Cache Direct / sec N/A Displays the rate of queries answered from the cache directly MSAS 2005: Storage Engine Query Queries from Cache Filtered / Sec N/A Displays the Rate of queries answered by filtering existing cache entry. MSAS 2005: Storage Engine Query Queries from File / Sec N/A Displays the Rate of queries answered from files. MSAS 2005: Storage Engine Query Average time /query N/A Displays the average time of a query MSAS 2005: Connection Current connections N/A Displays the number of connections against the SSAS instance MSAS 2005: Connection Requests / sec N/A Displays the rate of query requests per second MSAS 2005: Locks Current Lock Waits N/A Displays thhe number of connections waiting on a lock MSAS 2005: Threads Query Pool job queue Length N/A The number of queries in the job queue MSAS 2005:Proc Aggregations Temp file bytes written/sec N/A Shows the number of bytes of data processed in a temporary file MSAS 2005:Proc Aggregations Temp file rows written/sec N/A Shows the number of bytes of data processed in a temporary file 

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  • SQL SERVER – Weekly Series – Memory Lane – #032

    - by Pinal Dave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Complete Series of Database Coding Standards and Guidelines SQL SERVER Database Coding Standards and Guidelines – Introduction SQL SERVER – Database Coding Standards and Guidelines – Part 1 SQL SERVER – Database Coding Standards and Guidelines – Part 2 SQL SERVER Database Coding Standards and Guidelines Complete List Download Explanation and Example – SELF JOIN When all of the data you require is contained within a single table, but data needed to extract is related to each other in the table itself. Examples of this type of data relate to Employee information, where the table may have both an Employee’s ID number for each record and also a field that displays the ID number of an Employee’s supervisor or manager. To retrieve the data tables are required to relate/join to itself. Insert Multiple Records Using One Insert Statement – Use of UNION ALL This is very interesting question I have received from new developer. How can I insert multiple values in table using only one insert? Now this is interesting question. When there are multiple records are to be inserted in the table following is the common way using T-SQL. Function to Display Current Week Date and Day – Weekly Calendar Straight blog post with script to find current week date and day based on the parameters passed in the function.  2008 In my beginning years, I have almost same confusion as many of the developer had in their earlier years. Here are two of the interesting question which I have attempted to answer in my early year. Even if you are experienced developer may be you will still like to read following two questions: Order Of Column In Index Order of Conditions in WHERE Clauses Example of DISTINCT in Aggregate Functions Have you ever used DISTINCT with the Aggregation Function? Here is a simple example about how users can do it. Create a Comma Delimited List Using SELECT Clause From Table Column Straight to script example where I explained how to do something easy and quickly. Compound Assignment Operators SQL SERVER 2008 has introduced new concept of Compound Assignment Operators. Compound Assignment Operators are available in many other programming languages for quite some time. Compound Assignment Operators is operator where variables are operated upon and assigned on the same line. PIVOT and UNPIVOT Table Examples Here is a very interesting question – the answer to the question can be YES or NO both. “If we PIVOT any table and UNPIVOT that table do we get our original table?” Read the blog post to get the explanation of the question above. 2009 What is Interim Table – Simple Definition of Interim Table The interim table is a table that is generated by joining two tables and not the final result table. In other words, when two tables are joined they create an interim table as resultset but the resultset is not final yet. It may be possible that more tables are about to join on the interim table, and more operations are still to be applied on that table (e.g. Order By, Having etc). Besides, it may be possible that there is no interim table; sometimes final table is what is generated when the query is run. 2010 Stored Procedure and Transactions If Stored Procedure is transactional then, it should roll back complete transactions when it encounters any errors. Well, that does not happen in this case, which proves that Stored Procedure does not only provide just the transactional feature to a batch of T-SQL. Generate Database Script for SQL Azure When talking about SQL Azure the most common complaint I hear is that the script generated from stand-along SQL Server database is not compatible with SQL Azure. This was true for some time for sure but not any more. If you have SQL Server 2008 R2 installed you can follow the guideline below to generate a script which is compatible with SQL Azure. Convert IN to EXISTS – Performance Talk It is NOT necessary that every time when IN is replaced by EXISTS it gives better performance. However, in our case listed above it does for sure give better performance. You can read about this subject in the associated blog post. Subquery or Join – Various Options – SQL Server Engine Knows the Best Every single time whenever there is a performance tuning exercise, I hear the conversation from developer where some prefer subquery and some prefer join. In this two part blog post, I explain the same in the detail with examples. Part 1 | Part 2 Merge Operations – Insert, Update, Delete in Single Execution MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. 2011 Puzzle – Statistics are not updated but are Created Once Here is the quick scenario about my setup. Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated – WHY? Question to You – When to use Function and When to use Stored Procedure Personally, I believe that they are both different things - they cannot be compared. I can say, it will be like comparing apples and oranges. Each has its own unique use. However, they can be used interchangeably at many times and in real life (i.e., production environment). I have personally seen both of these being used interchangeably many times. This is the precise reason for asking this question. 2012 In year 2012 I had two interesting series ran on the blog. If there is no fun in learning, the learning becomes a burden. For the same reason, I had decided to build a three part quiz around SEQUENCE. The quiz was to identify the next value of the sequence. I encourage all of you to take part in this fun quiz. Guess the Next Value – Puzzle 1 Guess the Next Value – Puzzle 2 Guess the Next Value – Puzzle 3 Guess the Next Value – Puzzle 4 Simple Example to Configure Resource Governor – Introduction to Resource Governor Resource Governor is a feature which can manage SQL Server Workload and System Resource Consumption. We can limit the amount of CPU and memory consumption by limiting /governing /throttling on the SQL Server. If there are different workloads running on SQL Server and each of the workload needs different resources or when workloads are competing for resources with each other and affecting the performance of the whole server resource governor is a very important task. Tricks to Replace SELECT * with Column Names – SQL in Sixty Seconds #017 – Video  Retrieves unnecessary columns and increases network traffic When a new columns are added views needs to be refreshed manually Leads to usage of sub-optimal execution plan Uses clustered index in most of the cases instead of using optimal index It is difficult to debug SQL SERVER – Load Generator – Free Tool From CodePlex The best part of this SQL Server Load Generator is that users can run multiple simultaneous queries again SQL Server using different login account and different application name. The interface of the tool is extremely easy to use and very intuitive as well. A Puzzle – Swap Value of Column Without Case Statement Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Integrating Oracle Hyperion Smart View Data Queries with MS Word and Power Point

    - by Andreea Vaduva
    Untitled Document table { border: thin solid; } Most Smart View users probably appreciate that they can use just one add-in to access data from the different sources they might work with, like Oracle Essbase, Oracle Hyperion Planning, Oracle Hyperion Financial Management and others. But not all of them are aware of the options to integrate data analyses not only in Excel, but also in MS Word or Power Point. While in the past, copying and pasting single numbers or tables from a recent analysis in Excel made the pasted content a static snapshot, copying so called Data Points now creates dynamic, updateable references to the data source. It also provides additional nice features, which can make life easier and less stressful for Smart View users. So, how does this option work: after building an ad-hoc analysis with Smart View as usual in an Excel worksheet, any area including data cells/numbers from the database can be highlighted in order to copy data points - even single data cells only.   TIP It is not necessary to highlight and copy the row or column descriptions   Next from the Smart View ribbon select Copy Data Point. Then transfer to the Word or Power Point document into which the selected content should be copied. Note that in these Office programs you will find a menu item Smart View;from it select the Paste Data Point icon. The copied details from the Excel report will be pasted, but showing #NEED_REFRESH in the data cells instead of the original numbers. =After clicking the Refresh icon on the Smart View menu the data will be retrieved and displayed. (Maybe at that moment a login window pops up and you need to provide your credentials.) It works in the same way if you just copy one single number without any row or column descriptions, for example in order to incorporate it into a continuous text: Before refresh: After refresh: From now on for any subsequent updates of the data shown in your documents you only need to refresh data by clicking the Refresh button on the Smart View menu, without copying and pasting the context or content again. As you might realize, trying out this feature on your own, there won’t be any Point of View shown in the Office document. Also you have seen in the example, where only a single data cell was copied, that there aren’t any member names or row/column descriptions copied, which are usually required in an ad-hoc report in order to exactly define where data comes from or how data is queried from the source. Well, these definitions are not visible, but they are transferred to the Word or Power Point document as well. They are stored in the background for each individual data cell copied and can be made visible by double-clicking the data cell as shown in the following screen shot (but which is taken from another context).   So for each cell/number the complete connection information is stored along with the exact member/cell intersection from the database. And that’s not all: you have the chance now to exchange the members originally selected in the Point of View (POV) in the Excel report. Remember, at that time we had the following selection:   By selecting the Manage POV option from the Smart View meny in Word or Power Point…   … the following POV Manager – Queries window opens:   You can now change your selection for each dimension from the original POV by either double-clicking the dimension member in the lower right box under POV: or by selecting the Member Selector icon on the top right hand side of the window. After confirming your changes you need to refresh your document again. Be aware, that this will update all (!) numbers taken from one and the same original Excel sheet, even if they appear in different locations in your Office document, reflecting your recent changes in the POV. TIP Build your original report already in a way that dimensions you might want to change from within Word or Power Point are placed in the POV. And there is another really nice feature I wouldn’t like to miss mentioning: Using Dynamic Data Points in the way described above, you will never miss or need to search again for your original Excel sheet from which values were taken and copied as data points into an Office document. Because from even only one single data cell Smart View is able to recreate the entire original report content with just a few clicks: Select one of the numbers from within your Word or Power Point document by double-clicking.   Then select the Visualize in Excel option from the Smart View menu. Excel will open and Smart View will rebuild the entire original report, including POV settings, and retrieve all data from the most recent actual state of the database. (It might be necessary to provide your credentials before data is displayed.) However, in order to make this work, an active online connection to your databases on the server is necessary and at least read access to the retrieved data. But apart from this, your newly built Excel report is fully functional for ad-hoc analysis and can be used in the common way for drilling, pivoting and all the other known functions and features. So far about embedding Dynamic Data Points into Office documents and linking them back into Excel worksheets. You can apply this in the described way with ad-hoc analyses directly on Essbase databases or using Hyperion Planning and Hyperion Financial Management ad-hoc web forms. If you are also interested in other new features and smart enhancements in Essbase or Hyperion Planning stay tuned for coming articles or check our training courses and web presentations. You can find general information about offerings for the Essbase and Planning curriculum or other Oracle-Hyperion products here (please make sure to select your country/region at the top of this page) or in the OU Learning paths section , where Planning, Essbase and other Hyperion products can be found under the Fusion Middleware heading (again, please select the right country/region). Or drop me a note directly: [email protected] . About the Author: Bernhard Kinkel started working for Hyperion Solutions as a Presales Consultant and Consultant in 1998 and moved to Hyperion Education Services in 1999. He joined Oracle University in 2007 where he is a Principal Education Consultant. Based on these many years of working with Hyperion products he has detailed product knowledge across several versions. He delivers both classroom and live virtual courses. His areas of expertise are Oracle/Hyperion Essbase, Oracle Hyperion Planning and Hyperion Web Analysis.  

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  • Poner aplicaci&oacute;n Asp.Net en modo OFFLINE

    - by Jason Ulloa
    Una de las opciones que todo aplicación debería tener es el poder ponerse en modo OFFLINE para evitar el acceso de usuarios. Esto es completamente necesario cuando queremos realizar cambios a nuestra aplicación (cambiar algo, poner una actualización, etc) o a nuestra base de datos y evitarnos problemas con los usuarios que se encuentren logueados dentro de la aplicación en ese momento. Muchos ejemplos a través de la Web exponen la forma de realizar esta tarea utilizando dos técnicas: 1. La primera de ellas es utilizar el archivo App_Offline.htm sin embargo, esta técnica tiene un inconveniente. Y es que, una vez que hemos subido el archivo a nuestra aplicación esta se bloquea completamente y no tenemos forma de volver a ponerla ONLINE a menos que eliminemos el archivo. Es decir no podemos controlarla. 2. La segunda de ellas es el utilizar la etiqueta httpRuntime, pero nuevamente tenemos el mismo problema. Al habilitar el modo OFFLINE mediante esta etiqueta, tampoco podremos acceder a un modo de administración para cambiarla. Un ejemplo de la etiqueta httpRuntime <configuration> <system.web> <httpRuntime enable="false" /> </system.web> </configuration>   Tomando en cuenta lo anterior, lo mas optimo seria que podamos por medio de alguna pagina de administración colocar nuestro sitio en modo OFFLINE, pero manteniendo el acceso a la pagina de administración para poder volver a cambiar el valor que pondrá nuestra aplicación nuevamente en modo ONLINE. Para ello, utilizaremos el web.config de nuestra aplicación y una pequeña clase que se encargara de Leer y escribir los valores. Lo primero será, abrir nuestro web.config y definir dentro del appSettings dos nuevas KEY que contendrán los valores para el modo OFFLINE de nuestra aplicación: <appSettings> <add key="IsOffline" value="false" /> <add key="IsOfflineMessage" value="Sistema temporalmente no disponible por tareas de mantenimiento." /> </appSettings>   En las KEY anteriores tenemos el IsOffLine con value de false, esto es para indicarle a nuestra aplicación que actualmente su modo de funcionamiento es ONLINE, este valor será el que posteriormente cambiemos a TRUE para volver al modo OFFLINE. Nuestra segunda KEY (IsOfflineMessage) posee el value (Sistema temporalmente….) que será mostrado al usuario como un mensaje cuando el sitio este en modo OFFLINE. Una vez definidas nuestras dos KEY en el web.config, escribiremos una clase personalizada para leer y escribir los valores. Así que, agregamos un nuevo elemento de tipo clase al proyecto llamado SettingsRules y la definimos como Public. Está clase contendrá dos métodos, el primero será para leer los valores: public string readIsOnlineSettings(string sectionToRead) { Configuration cfg = WebConfigurationManager.OpenWebConfiguration(System.Web.Hosting.HostingEnvironment.ApplicationVirtualPath); KeyValueConfigurationElement isOnlineSettings = (KeyValueConfigurationElement)cfg.AppSettings.Settings[sectionToRead]; return isOnlineSettings.Value; }   El segundo método, será el encargado de escribir los nuevos valores al web.config public bool saveIsOnlineSettings(string sectionToWrite, string value) { bool succesFullySaved;   try { Configuration cfg = WebConfigurationManager.OpenWebConfiguration(System.Web.Hosting.HostingEnvironment.ApplicationVirtualPath); KeyValueConfigurationElement repositorySettings = (KeyValueConfigurationElement)cfg.AppSettings.Settings[sectionToWrite];   if (repositorySettings != null) { repositorySettings.Value = value; cfg.Save(ConfigurationSaveMode.Modified); } succesFullySaved = true; } catch (Exception) { succesFullySaved = false; } return succesFullySaved; }   Por último, definiremos en nuestra clase una región llamada instance, que contendrá un método encargado de devolver una instancia de la clase (esto para no tener que hacerlo luego) #region instance   private static SettingsRules m_instance;   // Properties public static SettingsRules Instance { get { if (m_instance == null) { m_instance = new SettingsRules(); } return m_instance; } }   #endregion instance   Con esto, nuestra clase principal esta completa. Así que pasaremos a la implementación de las páginas y el resto de código que completará la funcionalidad.   Para complementar la tarea del web.config utilizaremos el fabuloso GLOBAL.ASAX, este contendrá el código encargado de detectar si nuestra aplicación tiene el valor de ONLINE o OFFLINE y además de bloquear todas las paginas y directorios excepto el que le hayamos definido como administrador, esto para luego poder volver a configurar el sitio.   El evento del Global.Asax que utilizaremos será el Application_BeginRequest   protected void Application_BeginRequest(Object sender, EventArgs e) {   if (Convert.ToBoolean(SettingsRules.Instance.readIsOnlineSettings("IsOffline"))) {   string Virtual = Request.Path.Substring(0, Request.Path.LastIndexOf("/") + 1);   if (Virtual.ToLower().IndexOf("/admin/") == -1) { //We don't makes action, is admin section Server.Transfer("~/TemporarilyOfflineMessage.aspx"); }   } } La primer Línea del IF, verifica si el atributo del web.config es True o False, si es true toma la dirección WEB que se ha solicitado y la incluimos en un IF para verificar si corresponde a la Sección admin (está sección no es mas que un folder en nuestra aplicación llamado admin y puede ser cambiado a cualquier otro). Si el resultado de ese if es –1 quiere decir que no coincide, entonces, esa será la bandera que nos permitirá bloquear inmediatamente la pagina actual, transfiriendo al usuario a una pagina de mantenimiento. Ahora, en nuestra carpeta Admin crearemos una nueva pagina asp.net llamada OnlineSettings.aspx para actualizar y leer los datos del web.config y una pagina Default.aspx para pruebas. Nuestra página OnlineSettings tendrá dos pasos importantes: 1. Leer los datos actuales de configuración protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { IsOffline.Checked = Convert.ToBoolean(mySettings.readIsOnlineSettings("IsOffline")); OfflineMessage.Text = mySettings.readIsOnlineSettings("IsOfflineMessage"); } }   2. Actualizar los datos con los nuevos valores. protected void UpdateButton_Click(object sender, EventArgs e) { string htmlMessage = OfflineMessage.Text.Replace(Environment.NewLine, "<br />");   // Update the Application variables Application.Lock(); if (IsOffline.Checked) { mySettings.saveIsOnlineSettings("IsOffline", "True"); mySettings.saveIsOnlineSettings("IsOfflineMessage", htmlMessage); } else { mySettings.saveIsOnlineSettings("IsOffline", "false"); mySettings.saveIsOnlineSettings("IsOfflineMessage", htmlMessage); }   Application.UnLock(); }   Por último en la raíz de la aplicación, crearemos una nueva página aspx llamada TemporarilyOfflineMessage.aspx que será la que se muestre cuando se bloquee la aplicación. Al final nuestra aplicación se vería algo así Página bloqueada Configuración del Bloqueo Y para terminar la aplicación de ejemplo

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  • Scheduling thread tiles with C++ AMP

    - by Daniel Moth
    This post assumes you are totally comfortable with, what some of us call, the simple model of C++ AMP, i.e. you could write your own matrix multiplication. We are now ready to explore the tiled model, which builds on top of the non-tiled one. Tiling the extent We know that when we pass a grid (which is just an extent under the covers) to the parallel_for_each call, it determines the number of threads to schedule and their index values (including dimensionality). For the single-, two-, and three- dimensional cases you can go a step further and subdivide the threads into what we call tiles of threads (others may call them thread groups). So here is a single-dimensional example: extent<1> e(20); // 20 units in a single dimension with indices from 0-19 grid<1> g(e);      // same as extent tiled_grid<4> tg = g.tile<4>(); …on the 3rd line we subdivided the single-dimensional space into 5 single-dimensional tiles each having 4 elements, and we captured that result in a concurrency::tiled_grid (a new class in amp.h). Let's move on swiftly to another example, in pictures, this time 2-dimensional: So we start on the left with a grid of a 2-dimensional extent which has 8*6=48 threads. We then have two different examples of tiling. In the first case, in the middle, we subdivide the 48 threads into tiles where each has 4*3=12 threads, hence we have 2*2=4 tiles. In the second example, on the right, we subdivide the original input into tiles where each has 2*2=4 threads, hence we have 4*3=12 tiles. Notice how you can play with the tile size and achieve different number of tiles. The numbers you pick must be such that the original total number of threads (in our example 48), remains the same, and every tile must have the same size. Of course, you still have no clue why you would do that, but stick with me. First, we should see how we can use this tiled_grid, since the parallel_for_each function that we know expects a grid. Tiled parallel_for_each and tiled_index It turns out that we have additional overloads of parallel_for_each that accept a tiled_grid instead of a grid. However, those overloads, also expect that the lambda you pass in accepts a concurrency::tiled_index (new in amp.h), not an index<N>. So how is a tiled_index different to an index? A tiled_index object, can have only 1 or 2 or 3 dimensions (matching exactly the tiled_grid), and consists of 4 index objects that are accessible via properties: global, local, tile_origin, and tile. The global index is the same as the index we know and love: the global thread ID. The local index is the local thread ID within the tile. The tile_origin index returns the global index of the thread that is at position 0,0 of this tile, and the tile index is the position of the tile in relation to the overall grid. Confused? Here is an example accompanied by a picture that hopefully clarifies things: array_view<int, 2> data(8, 6, p_my_data); parallel_for_each(data.grid.tile<2,2>(), [=] (tiled_index<2,2> t_idx) restrict(direct3d) { /* todo */ }); Given the code above and the picture on the right, what are the values of each of the 4 index objects that the t_idx variables exposes, when the lambda is executed by T (highlighted in the picture on the right)? If you can't work it out yourselves, the solution follows: t_idx.global       = index<2> (6,3) t_idx.local          = index<2> (0,1) t_idx.tile_origin = index<2> (6,2) t_idx.tile             = index<2> (3,1) Don't move on until you are comfortable with this… the picture really helps, so use it. Tiled Matrix Multiplication Example – part 1 Let's paste here the C++ AMP matrix multiplication example, bolding the lines we are going to change (can you guess what the changes will be?) 01: void MatrixMultiplyTiled_Part1(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W) 02: { 03: 04: array_view<const float,2> a(M, W, vA); 05: array_view<const float,2> b(W, N, vB); 06: array_view<writeonly<float>,2> c(M, N, vC); 07: parallel_for_each(c.grid, 08: [=](index<2> idx) restrict(direct3d) { 09: 10: int row = idx[0]; int col = idx[1]; 11: float sum = 0.0f; 12: for(int i = 0; i < W; i++) 13: sum += a(row, i) * b(i, col); 14: c[idx] = sum; 15: }); 16: } To turn this into a tiled example, first we need to decide our tile size. Let's say we want each tile to be 16*16 (which assumes that we'll have at least 256 threads to process, and that c.grid.extent.size() is divisible by 256, and moreover that c.grid.extent[0] and c.grid.extent[1] are divisible by 16). So we insert at line 03 the tile size (which must be a compile time constant). 03: static const int TS = 16; ...then we need to tile the grid to have tiles where each one has 16*16 threads, so we change line 07 to be as follows 07: parallel_for_each(c.grid.tile<TS,TS>(), ...that means that our index now has to be a tiled_index with the same characteristics as the tiled_grid, so we change line 08 08: [=](tiled_index<TS, TS> t_idx) restrict(direct3d) { ...which means, without changing our core algorithm, we need to be using the global index that the tiled_index gives us access to, so we insert line 09 as follows 09: index<2> idx = t_idx.global; ...and now this code just works and it is tiled! Closing thoughts on part 1 The process we followed just shows the mechanical transformation that can take place from the simple model to the tiled model (think of this as step 1). In fact, when we wrote the matrix multiplication example originally, the compiler was doing this mechanical transformation under the covers for us (and it has additional smarts to deal with the cases where the total number of threads scheduled cannot be divisible by the tile size). The point is that the thread scheduling is always tiled, even when you use the non-tiled model. But with this mechanical transformation, we haven't gained anything… Hint: our goal with explicitly using the tiled model is to gain even more performance. In the next post, we'll evolve this further (beyond what the compiler can automatically do for us, in this first release), so you can see the full usage of the tiled model and its benefits… Comments about this post by Daniel Moth welcome at the original blog.

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  • Annotation Processor for Superclass Sensitive Actions

    - by Geertjan
    Someone creating superclass sensitive actions should need to specify only the following things: The condition under which the popup menu item should be available, i.e., the condition under which the action is relevant. And, for superclass sensitive actions, the condition is the name of a superclass. I.e., if I'm creating an action that should only be invokable if the class implements "org.openide.windows.TopComponent",  then that fully qualified name is the condition. The position in the list of Java class popup menus where the new menu item should be found, relative to the existing menu items. The display name. The path to the action folder where the new action is registered in the Central Registry. The code that should be executed when the action is invoked. In other words, the code for the enablement (which, in this case, means the visibility of the popup menu item when you right-click on the Java class) should be handled generically, under the hood, and not every time all over again in each action that needs this special kind of enablement. So, here's the usage of my newly created @SuperclassBasedActionAnnotation, where you should note that the DataObject must be in the Lookup, since the action will only be available to be invoked when you right-click on a Java source file (i.e., text/x-java) in an explorer view: import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import org.netbeans.sbas.annotations.SuperclassBasedActionAnnotation; import org.openide.awt.StatusDisplayer; import org.openide.loaders.DataObject; import org.openide.util.NbBundle; import org.openide.util.Utilities; @SuperclassBasedActionAnnotation( position=30, displayName="#CTL_BrandTopComponentAction", path="File", type="org.openide.windows.TopComponent") @NbBundle.Messages("CTL_BrandTopComponentAction=Brand") public class BrandTopComponentAction implements ActionListener { private final DataObject context; public BrandTopComponentAction() { context = Utilities.actionsGlobalContext().lookup(DataObject.class); } @Override public void actionPerformed(ActionEvent ev) { String message = context.getPrimaryFile().getPath(); StatusDisplayer.getDefault().setStatusText(message); } } That implies I've created (in a separate module to where it is used) a new annotation. Here's the definition: package org.netbeans.sbas.annotations; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; @Retention(RetentionPolicy.SOURCE) @Target(ElementType.TYPE) public @interface SuperclassBasedActionAnnotation { String type(); String path(); int position(); String displayName(); } And here's the processor: package org.netbeans.sbas.annotations; import java.util.Set; import javax.annotation.processing.Processor; import javax.annotation.processing.RoundEnvironment; import javax.annotation.processing.SupportedAnnotationTypes; import javax.annotation.processing.SupportedSourceVersion; import javax.lang.model.SourceVersion; import javax.lang.model.element.Element; import javax.lang.model.element.TypeElement; import javax.lang.model.util.Elements; import org.openide.filesystems.annotations.LayerBuilder.File; import org.openide.filesystems.annotations.LayerGeneratingProcessor; import org.openide.filesystems.annotations.LayerGenerationException; import org.openide.util.lookup.ServiceProvider; @ServiceProvider(service = Processor.class) @SupportedAnnotationTypes("org.netbeans.sbas.annotations.SuperclassBasedActionAnnotation") @SupportedSourceVersion(SourceVersion.RELEASE_6) public class SuperclassBasedActionProcessor extends LayerGeneratingProcessor { @Override protected boolean handleProcess(Set annotations, RoundEnvironment roundEnv) throws LayerGenerationException { Elements elements = processingEnv.getElementUtils(); for (Element e : roundEnv.getElementsAnnotatedWith(SuperclassBasedActionAnnotation.class)) { TypeElement clazz = (TypeElement) e; SuperclassBasedActionAnnotation mpm = clazz.getAnnotation(SuperclassBasedActionAnnotation.class); String teName = elements.getBinaryName(clazz).toString(); String originalFile = "Actions/" + mpm.path() + "/" + teName.replace('.', '-') + ".instance"; File actionFile = layer(e).file( originalFile). bundlevalue("displayName", mpm.displayName()). methodvalue("instanceCreate", "org.netbeans.sbas.annotations.SuperclassSensitiveAction", "create"). stringvalue("type", mpm.type()). newvalue("delegate", teName); actionFile.write(); File javaPopupFile = layer(e).file( "Loaders/text/x-java/Actions/" + teName.replace('.', '-') + ".shadow"). stringvalue("originalFile", originalFile). intvalue("position", mpm.position()); javaPopupFile.write(); } return true; } } The "SuperclassSensitiveAction" referred to in the code above is unchanged from how I had it in yesterday's blog entry. When I build the module containing two action listeners that use my new annotation, the generated layer file looks as follows, which is identical to the layer file entries I hard coded yesterday: <folder name="Actions"> <folder name="File"> <file name="org-netbeans-sbas-impl-ActionListenerSensitiveAction.instance"> <attr name="displayName" stringvalue="Process Action Listener"/> <attr methodvalue="org.netbeans.sbas.annotations.SuperclassSensitiveAction.create" name="instanceCreate"/> <attr name="type" stringvalue="java.awt.event.ActionListener"/> <attr name="delegate" newvalue="org.netbeans.sbas.impl.ActionListenerSensitiveAction"/> </file> <file name="org-netbeans-sbas-impl-BrandTopComponentAction.instance"> <attr bundlevalue="org.netbeans.sbas.impl.Bundle#CTL_BrandTopComponentAction" name="displayName"/> <attr methodvalue="org.netbeans.sbas.annotations.SuperclassSensitiveAction.create" name="instanceCreate"/> <attr name="type" stringvalue="org.openide.windows.TopComponent"/> <attr name="delegate" newvalue="org.netbeans.sbas.impl.BrandTopComponentAction"/> </file> </folder> </folder> <folder name="Loaders"> <folder name="text"> <folder name="x-java"> <folder name="Actions"> <file name="org-netbeans-sbas-impl-ActionListenerSensitiveAction.shadow"> <attr name="originalFile" stringvalue="Actions/File/org-netbeans-sbas-impl-ActionListenerSensitiveAction.instance"/> <attr intvalue="10" name="position"/> </file> <file name="org-netbeans-sbas-impl-BrandTopComponentAction.shadow"> <attr name="originalFile" stringvalue="Actions/File/org-netbeans-sbas-impl-BrandTopComponentAction.instance"/> <attr intvalue="30" name="position"/> </file> </folder> </folder> </folder> </folder>

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  • How to use Ninject with XNA?

    - by Rosarch
    I'm having difficulty integrating Ninject with XNA. static class Program { /** * The main entry point for the application. */ static void Main(string[] args) { IKernel kernel = new StandardKernel(NinjectModuleManager.GetModules()); CachedContentLoader content = kernel.Get<CachedContentLoader>(); // stack overflow here MasterEngine game = kernel.Get<MasterEngine>(); game.Run(); } } // constructor for the game public MasterEngine(IKernel kernel) : base(kernel) { this.inputReader = kernel.Get<IInputReader>(); graphicsDeviceManager = kernel.Get<GraphicsDeviceManager>(); Components.Add(kernel.Get<GamerServicesComponent>()); // Tell the loader to look for all files relative to the "Content" directory. Assets = kernel.Get<CachedContentLoader>(); //Sets dimensions of the game window graphicsDeviceManager.PreferredBackBufferWidth = 800; graphicsDeviceManager.PreferredBackBufferHeight = 600; graphicsDeviceManager.ApplyChanges(); IsMouseVisible = false; } Ninject.cs: using System; using System.Collections.Generic; using System.Linq; using System.Text; using Ninject.Modules; using HWAlphaRelease.Controller; using Microsoft.Xna.Framework; using Nuclex.DependencyInjection.Demo.Scaffolding; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.Graphics; namespace HWAlphaRelease { public static class NinjectModuleManager { public static NinjectModule[] GetModules() { return new NinjectModule[1] { new GameModule() }; } /// <summary>Dependency injection rules for the main game instance</summary> public class GameModule : NinjectModule { #region class ServiceProviderAdapter /// <summary>Delegates to the game's built-in service provider</summary> /// <remarks> /// <para> /// When a class' constructor requires an IServiceProvider, the dependency /// injector cannot just construct a new one and wouldn't know that it has /// to create an instance of the Game class (or take it from the existing /// Game instance). /// </para> /// <para> /// The solution, then, is this small adapter that takes a Game instance /// and acts as if it was a freely constructable IServiceProvider implementation /// while in reality, it delegates all lookups to the Game's service container. /// </para> /// </remarks> private class ServiceProviderAdapter : IServiceProvider { /// <summary>Initializes a new service provider adapter for the game</summary> /// <param name="game">Game the service provider will be taken from</param> public ServiceProviderAdapter(Game game) { this.gameServices = game.Services; } /// <summary>Retrieves a service from the game service container</summary> /// <param name="serviceType">Type of the service that will be retrieved</param> /// <returns>The service that has been requested</returns> public object GetService(Type serviceType) { return this.gameServices; } /// <summary>Game services container of the Game instance</summary> private GameServiceContainer gameServices; } #endregion // class ServiceProviderAdapter #region class ContentManagerAdapter /// <summary>Delegates to the game's built-in ContentManager</summary> /// <remarks> /// This provides shared access to the game's ContentManager. A dependency /// injected class only needs to require the ISharedContentService in its /// constructor and the dependency injector will automatically resolve it /// to this adapter, which delegates to the Game's built-in content manager. /// </remarks> private class ContentManagerAdapter : ISharedContentService { /// <summary>Initializes a new shared content manager adapter</summary> /// <param name="game">Game the content manager will be taken from</param> public ContentManagerAdapter(Game game) { this.contentManager = game.Content; } /// <summary>Loads or accesses shared game content</summary> /// <typeparam name="AssetType">Type of the asset to be loaded or accessed</typeparam> /// <param name="assetName">Path and name of the requested asset</param> /// <returns>The requested asset from the the shared game content store</returns> public AssetType Load<AssetType>(string assetName) { return this.contentManager.Load<AssetType>(assetName); } /// <summary>The content manager this instance delegates to</summary> private ContentManager contentManager; } #endregion // class ContentManagerAdapter /// <summary>Initializes the dependency configuration</summary> public override void Load() { // Allows access to the game class for any components with a dependency // on the 'Game' or 'DependencyInjectionGame' classes. Bind<MasterEngine>().ToSelf().InSingletonScope(); Bind<NinjectGame>().To<MasterEngine>().InSingletonScope(); Bind<Game>().To<MasterEngine>().InSingletonScope(); // Let the dependency injector construct a graphics device manager for // all components depending on the IGraphicsDeviceService and // IGraphicsDeviceManager interfaces Bind<GraphicsDeviceManager>().ToSelf().InSingletonScope(); Bind<IGraphicsDeviceService>().To<GraphicsDeviceManager>().InSingletonScope(); Bind<IGraphicsDeviceManager>().To<GraphicsDeviceManager>().InSingletonScope(); // Some clever adapters that hand out the Game's IServiceProvider and allow // access to its built-in ContentManager Bind<IServiceProvider>().To<ServiceProviderAdapter>().InSingletonScope(); Bind<ISharedContentService>().To<ContentManagerAdapter>().InSingletonScope(); Bind<IInputReader>().To<UserInputReader>().InSingletonScope().WithConstructorArgument("keyMapping", Constants.DEFAULT_KEY_MAPPING); Bind<CachedContentLoader>().ToSelf().InSingletonScope().WithConstructorArgument("rootDir", "Content"); } } } } NinjectGame.cs /// <summary>Base class for Games making use of Ninject</summary> public class NinjectGame : Game { /// <summary>Initializes a new Ninject game instance</summary> /// <param name="kernel">Kernel the game has been created by</param> public NinjectGame(IKernel kernel) { Type ownType = this.GetType(); if(ownType != typeof(Game)) { kernel.Bind<NinjectGame>().To<MasterEngine>().InSingletonScope(); } kernel.Bind<Game>().To<NinjectGame>().InSingletonScope(); } } } // namespace Nuclex.DependencyInjection.Demo.Scaffolding When I try to get the CachedContentLoader, I get a stack overflow exception. I'm basing this off of this tutorial, but I really have no idea what I'm doing. Help?

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  • Announcing the release of the Windows Azure SDK 2.1 for .NET

    - by ScottGu
    Today we released the v2.1 update of the Windows Azure SDK for .NET.  This is a major refresh of the Windows Azure SDK and it includes some great new features and enhancements. These new capabilities include: Visual Studio 2013 Preview Support: The Windows Azure SDK now supports using the new VS 2013 Preview Visual Studio 2013 VM Image: Windows Azure now has a built-in VM image that you can use to host and develop with VS 2013 in the cloud Visual Studio Server Explorer Enhancements: Redesigned with improved filtering and auto-loading of subscription resources Virtual Machines: Start and Stop VM’s w/suspend billing directly from within Visual Studio Cloud Services: New Emulator Express option with reduced footprint and Run as Normal User support Service Bus: New high availability options, Notification Hub support, Improved VS tooling PowerShell Automation: Lots of new PowerShell commands for automating Web Sites, Cloud Services, VMs and more All of these SDK enhancements are now available to start using immediately and you can download the SDK from the Windows Azure .NET Developer Center.  Visual Studio’s Team Foundation Service (http://tfs.visualstudio.com/) has also been updated to support today’s SDK 2.1 release, and the SDK 2.1 features can now be used with it (including with automated builds + tests). Below are more details on the new features and capabilities released today: Visual Studio 2013 Preview Support Today’s Window Azure SDK 2.1 release adds support for the recent Visual Studio 2013 Preview. The 2.1 SDK also works with Visual Studio 2010 and Visual Studio 2012, and works side by side with the previous Windows Azure SDK 1.8 and 2.0 releases. To install the Windows Azure SDK 2.1 on your local computer, choose the “install the sdk” link from the Windows Azure .NET Developer Center. Then, chose which version of Visual Studio you want to use it with.  Clicking the third link will install the SDK with the latest VS 2013 Preview: If you don’t already have the Visual Studio 2013 Preview installed on your machine, this will also install Visual Studio Express 2013 Preview for Web. Visual Studio 2013 VM Image Hosted in the Cloud One of the requests we’ve heard from several customers has been to have the ability to host Visual Studio within the cloud (avoiding the need to install anything locally on your computer). With today’s SDK update we’ve added a new VM image to the Windows Azure VM Gallery that has Visual Studio Ultimate 2013 Preview, SharePoint 2013, SQL Server 2012 Express and the Windows Azure 2.1 SDK already installed on it.  This provides a really easy way to create a development environment in the cloud with the latest tools. With the recent shutdown and suspend billing feature we shipped on Windows Azure last month, you can spin up the image only when you want to do active development, and then shut down the virtual machine and not have to worry about usage charges while the virtual machine is not in use. You can create your own VS image in the cloud by using the New->Compute->Virtual Machine->From Gallery menu within the Windows Azure Management Portal, and then by selecting the “Visual Studio Ultimate 2013 Preview” template: Visual Studio Server Explorer: Improved Filtering/Management of Subscription Resources With the Windows Azure SDK 2.1 release you’ll notice significant improvements in the Visual Studio Server Explorer. The explorer has been redesigned so that all Windows Azure services are now contained under a single Windows Azure node.  From the top level node you can now manage your Windows Azure credentials, import a subscription file or filter Server Explorer to only show services from particular subscriptions or regions. Note: The Web Sites and Mobile Services nodes will appear outside the Windows Azure Node until the final release of VS 2013. If you have installed the ASP.NET and Web Tools Preview Refresh, though, the Web Sites node will appear inside the Windows Azure node even with the VS 2013 Preview. Once your subscription information is added, Windows Azure services from all your subscriptions are automatically enumerated in the Server Explorer. You no longer need to manually add services to Server Explorer individually. This provides a convenient way of viewing all of your cloud services, storage accounts, service bus namespaces, virtual machines, and web sites from one location: Subscription and Region Filtering Support Using the Windows Azure node in Server Explorer, you can also now filter your Windows Azure services in the Server Explorer by the subscription or region they are in.  If you have multiple subscriptions but need to focus your attention to just a few subscription for some period of time, this a handy way to hide the services from other subscriptions view until they become relevant. You can do the same sort of filtering by region. To enable this, just select “Filter Services” from the context menu on the Windows Azure node: Then choose the subscriptions and/or regions you want to filter by. In the below example, I’ve decided to show services from my pay-as-you-go subscription within the East US region: Visual Studio will then automatically filter the items that show up in the Server Explorer appropriately: With storage accounts and service bus namespaces, you sometimes need to work with services outside your subscription. To accommodate that scenario, those services allow you to attach an external account (from the context menu). You’ll notice that external accounts have a slightly different icon in server explorer to indicate they are from outside your subscription. Other Improvements We’ve also improved the Server Explorer by adding additional properties and actions to the service exposed. You now have access to most of the properties on a cloud service, deployment slot, role or role instance as well as the properties on storage accounts, virtual machines and web sites. Just select the object of interest in Server Explorer and view the properties in the property pane. We also now have full support for creating/deleting/update storage tables, blobs and queues from directly within Server Explorer.  Simply right-click on the appropriate storage account node and you can create them directly within Visual Studio: Virtual Machines: Start/Stop within Visual Studio Virtual Machines now have context menu actions that allow you start, shutdown, restart and delete a Virtual Machine directly within the Visual Studio Server Explorer. The shutdown action enables you to shut down the virtual machine and suspend billing when the VM is not is use, and easily restart it when you need it: This is especially useful in Dev/Test scenarios where you can start a VM – such as a SQL Server – during your development session and then shut it down / suspend billing when you are not developing (and no longer be billed for it). You can also now directly remote desktop into VMs using the “Connect using Remote Desktop” context menu command in VS Server Explorer.  Cloud Services: Emulator Express with Run as Normal User Support You can now launch Visual Studio and run your cloud services locally as a Normal User (without having to elevate to an administrator account) using a new Emulator Express option included as a preview feature with this SDK release.  Emulator Express is a version of the Windows Azure Compute Emulator that runs a restricted mode – one instance per role – and it doesn’t require administrative permissions and uses 40% less resources than the full Windows Azure Emulator. Emulator Express supports both web and worker roles. To run your application locally using the Emulator Express option, simply change the following settings in the Windows Azure project. On the shortcut menu for the Windows Azure project, choose Properties, and then choose the Web tab. Check the setting for IIS (Internet Information Services). Make sure that the option is set to IIS Express, not the full version of IIS. Emulator Express is not compatible with full IIS. On the Web tab, choose the option for Emulator Express. Service Bus: Notification Hubs With the Windows Azure SDK 2.1 release we are adding support for Windows Azure Notification Hubs as part of our official Windows Azure SDK, inside of Microsoft.ServiceBus.dll (previously the Notification Hub functionality was in a preview assembly). You are now able to create, update and delete Notification Hubs programmatically, manage your device registrations, and send push notifications to all your mobile clients across all platforms (Windows Store, Windows Phone 8, iOS, and Android). Learn more about Notification Hubs on MSDN here, or watch the Notification Hubs //BUILD/ presentation here. Service Bus: Paired Namespaces One of the new features included with today’s Windows Azure SDK 2.1 release is support for Service Bus “Paired Namespaces”.  Paired Namespaces enable you to better handle situations where a Service Bus service namespace becomes unavailable (for example: due to connectivity issues or an outage) and you are unable to send or receive messages to the namespace hosting the queue, topic, or subscription. Previously,to handle this scenario you had to manually setup separate namespaces that can act as a backup, then implement manual failover and retry logic which was sometimes tricky to get right. Service Bus now supports Paired Namespaces, which enables you to connect two namespaces together. When you activate the secondary namespace, messages are stored in the secondary queue for delivery to the primary queue at a later time. If the primary container (namespace) becomes unavailable for some reason, automatic failover enables the messages in the secondary queue. For detailed information about paired namespaces and high availability, see the new topic Asynchronous Messaging Patterns and High Availability. Service Bus: Tooling Improvements In this release, the Windows Azure Tools for Visual Studio contain several enhancements and changes to the management of Service Bus messaging entities using Visual Studio’s Server Explorer. The most noticeable change is that the Service Bus node is now integrated into the Windows Azure node, and supports integrated subscription management. Additionally, there has been a change to the code generated by the Windows Azure Worker Role with Service Bus Queue project template. This code now uses an event-driven “message pump” programming model using the QueueClient.OnMessage method. PowerShell: Tons of New Automation Commands Since my last blog post on the previous Windows Azure SDK 2.0 release, we’ve updated Windows Azure PowerShell (which is a separate download) five times. You can find the full change log here. We’ve added new cmdlets in the following areas: China instance and Windows Azure Pack support Environment Configuration VMs Cloud Services Web Sites Storage SQL Azure Service Bus China Instance and Windows Azure Pack We now support the following cmdlets for the China instance and Windows Azure Pack, respectively: China Instance: Web Sites, Service Bus, Storage, Cloud Service, VMs, Network Windows Azure Pack: Web Sites, Service Bus We will have full cmdlet support for these two Windows Azure environments in PowerShell in the near future. Virtual Machines: Stop/Start Virtual Machines Similar to the Start/Stop VM capability in VS Server Explorer, you can now stop your VM and suspend billing: If you want to keep the original behavior of keeping your stopped VM provisioned, you can pass in the -StayProvisioned switch parameter. Virtual Machines: VM endpoint ACLs We’ve added and updated a bunch of cmdlets for you to configure fine-grained network ACL on your VM endpoints. You can use the following cmdlets to create ACL config and apply them to a VM endpoint: New-AzureAclConfig Get-AzureAclConfig Set-AzureAclConfig Remove-AzureAclConfig Add-AzureEndpoint -ACL Set-AzureEndpoint –ACL The following example shows how to add an ACL rule to an existing endpoint of a VM. Other improvements for Virtual Machine management includes Added -NoWinRMEndpoint parameter to New-AzureQuickVM and Add-AzureProvisioningConfig to disable Windows Remote Management Added -DirectServerReturn parameter to Add-AzureEndpoint and Set-AzureEndpoint to enable/disable direct server return Added Set-AzureLoadBalancedEndpoint cmdlet to modify load balanced endpoints Cloud Services: Remote Desktop and Diagnostics Remote Desktop and Diagnostics are popular debugging options for Cloud Services. We’ve introduced cmdlets to help you configure these two Cloud Service extensions from Windows Azure PowerShell. Windows Azure Cloud Services Remote Desktop extension: New-AzureServiceRemoteDesktopExtensionConfig Get-AzureServiceRemoteDesktopExtension Set-AzureServiceRemoteDesktopExtension Remove-AzureServiceRemoteDesktopExtension Windows Azure Cloud Services Diagnostics extension New-AzureServiceDiagnosticsExtensionConfig Get-AzureServiceDiagnosticsExtension Set-AzureServiceDiagnosticsExtension Remove-AzureServiceDiagnosticsExtension The following example shows how to enable Remote Desktop for a Cloud Service. Web Sites: Diagnostics With our last SDK update, we introduced the Get-AzureWebsiteLog –Tail cmdlet to get the log streaming of your Web Sites. Recently, we’ve also added cmdlets to configure Web Site application diagnostics: Enable-AzureWebsiteApplicationDiagnostic Disable-AzureWebsiteApplicationDiagnostic The following 2 examples show how to enable application diagnostics to the file system and a Windows Azure Storage Table: SQL Database Previously, you had to know the SQL Database server admin username and password if you want to manage the database in that SQL Database server. Recently, we’ve made the experience much easier by not requiring the admin credential if the database server is in your subscription. So you can simply specify the -ServerName parameter to tell Windows Azure PowerShell which server you want to use for the following cmdlets. Get-AzureSqlDatabase New-AzureSqlDatabase Remove-AzureSqlDatabase Set-AzureSqlDatabase We’ve also added a -AllowAllAzureServices parameter to New-AzureSqlDatabaseServerFirewallRule so that you can easily add a firewall rule to whitelist all Windows Azure IP addresses. Besides the above experience improvements, we’ve also added cmdlets get the database server quota and set the database service objective. Check out the following cmdlets for details. Get-AzureSqlDatabaseServerQuota Get-AzureSqlDatabaseServiceObjective Set-AzureSqlDatabase –ServiceObjective Storage and Service Bus Other new cmdlets include Storage: CRUD cmdlets for Azure Tables and Queues Service Bus: Cmdlets for managing authorization rules on your Service Bus Namespace, Queue, Topic, Relay and NotificationHub Summary Today’s release includes a bunch of great features that enable you to build even better cloud solutions.  All the above features/enhancements are shipped and available to use immediately as part of the 2.1 release of the Windows Azure SDK for .NET. If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using all of the above features today.  Then visit the Windows Azure Developer Center to learn more about how to build apps with it. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • The Inkremental Architect&acute;s Napkin - #4 - Make increments tangible

    - by Ralf Westphal
    Originally posted on: http://geekswithblogs.net/theArchitectsNapkin/archive/2014/06/12/the-inkremental-architectacutes-napkin---4---make-increments-tangible.aspxThe driver of software development are increments, small increments, tiny increments. With an increment being a slice of the overall requirement scope thin enough to implement and get feedback from a product owner within 2 days max. Such an increment might concern Functionality or Quality.[1] To make such high frequency delivery of increments possible, the transition from talking to coding needs to be as easy as possible. A user story or some other documentation of what´s supposed to get implemented until tomorrow evening at latest is one side of the medal. The other is where to put the logic in all of the code base. To implement an increment, only logic statements are needed. Functionality like Quality are just about expressions and control flow statements. Think of Assembler code without the CALL/RET instructions. That´s all is needed. Forget about functions, forget about classes. To make a user happy none of that is really needed. It´s just about the right expressions and conditional executions paths plus some memory allocation. Automatic function inlining of compilers which makes it clear how unimportant functions are for delivering value to users at runtime. But why then are there functions? Because they were invented for optimization purposes. We need them for better Evolvability and Production Efficiency. Nothing more, nothing less. No software has become faster, more secure, more scalable, more functional because we gathered logic under the roof of a function or two or a thousand. Functions make logic easier to understand. Functions make us faster in producing logic. Functions make it easier to keep logic consistent. Functions help to conserve memory. That said, functions are important. They are even the pivotal element of software development. We can´t code without them - whether you write a function yourself or not. Because there´s always at least one function in play: the Entry Point of a program. In Ruby the simplest program looks like this:puts "Hello, world!" In C# more is necessary:class Program { public static void Main () { System.Console.Write("Hello, world!"); } } C# makes the Entry Point function explicit, not so Ruby. But still it´s there. So you can think of logic always running in some function. Which brings me back to increments: In order to make the transition from talking to code as easy as possible, it has to be crystal clear into which function you should put the logic. Product owners might be content once there is a sticky note a user story on the Scrum or Kanban board. But developers need an idea of what that sticky note means in term of functions. Because with a function in hand, with a signature to run tests against, they have something to focus on. All´s well once there is a function behind whose signature logic can be piled up. Then testing frameworks can be used to check if the logic is correct. Then practices like TDD can help to drive the implementation. That´s why most code katas define exactly how the API of a solution should look like. It´s a function, maybe two or three, not more. A requirement like “Write a function f which takes this as parameters and produces such and such output by doing x” makes a developer comfortable. Yes, there are all kinds of details to think about, like which algorithm or technology to use, or what kind of state and side effects to consider. Even a single function not only must deliver on Functionality, but also on Quality and Evolvability. Nevertheless, once it´s clear which function to put logic in, you have a tangible starting point. So, yes, what I´m suggesting is to find a single function to put all the logic in that´s necessary to deliver on a the requirements of an increment. Or to put it the other way around: Slice requirements in a way that each increment´s logic can be located under the roof of a single function. Entry points Of course, the logic of a software will always be spread across many, many functions. But there´s always an Entry Point. That´s the most important function for each increment, because that´s the root to put integration or even acceptance tests on. A batch program like the above hello-world application only has a single Entry Point. All logic is reached from there, regardless how deep it´s nested in classes. But a program with a user interface like this has at least two Entry Points: One is the main function called upon startup. The other is the button click event handler for “Show my score”. But maybe there are even more, like another Entry Point being a handler for the event fired when one of the choices gets selected; because then some logic could check if the button should be enabled because all questions got answered. Or another Entry Point for the logic to be executed when the program is close; because then the choices made should be persisted. You see, an Entry Point to me is a function which gets triggered by the user of a software. With batch programs that´s the main function. With GUI programs on the desktop that´s event handlers. With web programs that´s handlers for URL routes. And my basic suggestion to help you with slicing requirements for Spinning is: Slice them in a way so that each increment is related to only one Entry Point function.[2] Entry Points are the “outer functions” of a program. That´s where the environment triggers behavior. That´s where hardware meets software. Entry points always get called because something happened to hardware state, e.g. a key was pressed, a mouse button clicked, the system timer ticked, data arrived over a wire.[3] Viewed from the outside, software is just a collection of Entry Point functions made accessible via buttons to press, menu items to click, gestures, URLs to open, keys to enter. Collections of batch processors I´d thus say, we haven´t moved forward since the early days of software development. We´re still writing batch programs. Forget about “event-driven programming” with its fancy GUI applications. Software is just a collection of batch processors. Earlier it was just one per program, today it´s hundreds we bundle up into applications. Each batch processor is represented by an Entry Point as its root that works on a number of resources from which it reads data to process and to which it writes results. These resources can be the keyboard or main memory or a hard disk or a communication line or a display. Together many batch processors - large and small - form applications the user perceives as a single whole: Software development that way becomes quite simple: just implement one batch processor after another. Well, at least in principle ;-) Features Each batch processor entered through an Entry Point delivers value to the user. It´s an increment. Sometimes its logic is trivial, sometimes it´s very complex. Regardless, each Entry Point represents an increment. An Entry Point implemented thus is a step forward in terms of Agility. At the same time it´s a tangible unit for developers. Therefore, identifying the more or less numerous batch processors in a software system is a rewarding task for product owners and developers alike. That´s where user stories meet code. In this example the user story translates to the Entry Point triggered by clicking the login button on a dialog like this: The batch then retrieves what has been entered via keyboard, loads data from a user store, and finally outputs some kind of response on the screen, e.g. by displaying an error message or showing the next dialog. This is all very simple, but you see, there is not just one thing happening, but several. Get input (email address, password) Load user for email address If user not found report error Check password Hash password Compare hash to hash stored in user Show next dialog Viewed from 10,000 feet it´s all done by the Entry Point function. And of course that´s technically possible. It´s just a bunch of logic and calling a couple of API functions. However, I suggest to take these steps as distinct aspects of the overall requirement described by the user story. Such aspects of requirements I call Features. Features too are increments. Each provides some (small) value of its own to the user. Each can be checked individually by a product owner. Instead of implementing all the logic behind the Login() entry point at once you can move forward increment by increment, e.g. First implement the dialog, let the user enter any credentials, and log him/her in without any checks. Features 1 and 4. Then hard code a single user and check the email address. Features 2 and 2.1. Then check password without hashing it (or use a very simple hash like the length of the password). Features 3. and 3.2 Replace hard coded user with a persistent user directoy, but a very simple one, e.g. a CSV file. Refinement of feature 2. Calculate the real hash for the password. Feature 3.1. Switch to the final user directory technology. Each feature provides an opportunity to deliver results in a short amount of time and get feedback. If you´re in doubt whether you can implement the whole entry point function until tomorrow night, then just go for a couple of features or even just one. That´s also why I think, you should strive for wrapping feature logic into a function of its own. It´s a matter of Evolvability and Production Efficiency. A function per feature makes the code more readable, since the language of requirements analysis and design is carried over into implementation. It makes it easier to apply changes to features because it´s clear where their logic is located. And finally, of course, it lets you re-use features in different context (read: increments). Feature functions make it easier for you to think of features as Spinning increments, to implement them independently, to let the product owner check them for acceptance individually. Increments consist of features, entry point functions consist of feature functions. So you can view software as a hierarchy of requirements from broad to thin which map to a hierarchy of functions - with entry points at the top.   I like this image of software as a self-similar structure on many levels of abstraction where requirements and code match each other. That to me is true agile design: the core tenet of Agility to move forward in increments is carried over into implementation. Increments on paper are retained in code. This way developers can easily relate to product owners. Elusive and fuzzy requirements are not tangible. Software production is moving forward through requirements one increment at a time, and one function at a time. In closing Product owners and developers are different - but they need to work together towards a shared goal: working software. So their notions of software need to be made compatible, they need to be connected. The increments of the product owner - user stories and features - need to be mapped straightforwardly to something which is relevant to developers. To me that´s functions. Yes, functions, not classes nor components nor micro services. We´re talking about behavior, actions, activities, processes. Their natural representation is a function. Something has to be done. Logic has to be executed. That´s the purpose of functions. Later, classes and other containers are needed to stay on top of a growing amount of logic. But to connect developers and product owners functions are the appropriate glue. Functions which represent increments. Can there always be such a small increment be found to deliver until tomorrow evening? I boldly say yes. Yes, it´s always possible. But maybe you´ve to start thinking differently. Maybe the product owner needs to start thinking differently. Completion is not the goal anymore. Neither is checking the delivery of an increment through the user interface of a software. Product owners need to become comfortable using test beds for certain features. If it´s hard to slice requirements thin enough for Spinning the reason is too little knowledge of something. Maybe you don´t yet understand the problem domain well enough? Maybe you don´t yet feel comfortable with some tool or technology? Then it´s time to acknowledge this fact. Be honest about your not knowing. And instead of trying to deliver as a craftsman officially become a researcher. Research an check back with the product owner every day - until your understanding has grown to a level where you are able to define the next Spinning increment. ? Sometimes even thin requirement slices will cover several Entry Points, like “Add validation of email addresses to all relevant dialogs.” Validation then will it put into a dozen functons. Still, though, it´s important to determine which Entry Points exactly get affected. That´s much easier, if strive for keeping the number of Entry Points per increment to 1. ? If you like call Entry Point functions event handlers, because that´s what they are. They all handle events of some kind, whether that´s palpable in your code or note. A public void btnSave_Click(object sender, EventArgs e) {…} might look like an event handler to you, but public static void Main() {…} is one also - for then event “program started”. ?

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  • Flow-Design Cheat Sheet &ndash; Part I, Notation

    - by Ralf Westphal
    You want to avoid the pitfalls of object oriented design? Then this is the right place to start. Use Flow-Oriented Analysis (FOA) and –Design (FOD or just FD for Flow-Design) to understand a problem domain and design a software solution. Flow-Orientation as described here is related to Flow-Based Programming, Event-Based Programming, Business Process Modelling, and even Event-Driven Architectures. But even though “thinking in flows” is not new, I found it helpful to deviate from those precursors for several reasons. Some aim at too big systems for the average programmer, some are concerned with only asynchronous processing, some are even not very much concerned with programming at all. What I was looking for was a design method to help in software projects of any size, be they large or tiny, involing synchronous or asynchronous processing, being local or distributed, running on the web or on the desktop or on a smartphone. That´s why I took ideas from all of the above sources and some additional and came up with Event-Based Components which later got repositioned and renamed to Flow-Design. In the meantime this has generated some discussion (in the German developer community) and several teams have started to work with Flow-Design. Also I´ve conducted quite some trainings using Flow-Orientation for design. The results are very promising. Developers find it much easier to design software using Flow-Orientation than OOAD-based object orientation. Since Flow-Orientation is moving fast and is not covered completely by a single source like a book, demand has increased for at least an overview of the current state of its notation. This page is trying to answer this demand by briefly introducing/describing every notational element as well as their translation into C# source code. Take this as a cheat sheet to put next to your whiteboard when designing software. However, please do not expect any explanation as to the reasons behind Flow-Design elements. Details on why Flow-Design at all and why in this specific way you´ll find in the literature covering the topic. Here´s a resource page on Flow-Design/Event-Based Components, if you´re able to read German. Notation Connected Functional Units The basic element of any FOD are functional units (FU): Think of FUs as some kind of software code block processing data. For the moment forget about classes, methods, “components”, assemblies or whatever. See a FU as an abstract piece of code. Software then consists of just collaborating FUs. I´m using circles/ellipses to draw FUs. But if you like, use rectangles. Whatever suites your whiteboard needs best.   The purpose of FUs is to process input and produce output. FUs are transformational. However, FUs are not called and do not call other FUs. There is no dependency between FUs. Data just flows into a FU (input) and out of it (output). From where and where to is of no concern to a FU.   This way FUs can be concatenated in arbitrary ways:   Each FU can accept input from many sources and produce output for many sinks:   Flows Connected FUs form a flow with a start and an end. Data is entering a flow at a source, and it´s leaving it through a sink. Think of sources and sinks as special FUs which conntect wires to the environment of a network of FUs.   Wiring Details Data is flowing into/out of FUs through wires. This is to allude to electrical engineering which since long has been working with composable parts. Wires are attached to FUs usings pins. They are the entry/exit points for the data flowing along the wires. Input-/output pins currently need not be drawn explicitly. This is to keep designing on a whiteboard simple and quick.   Data flowing is of some type, so wires have a type attached to them. And pins have names. If there is only one input pin and output pin on a FU, though, you don´t need to mention them. The default is Process for a single input pin, and Result for a single output pin. But you´re free to give even single pins different names.   There is a shortcut in use to address a certain pin on a destination FU:   The type of the wire is put in parantheses for two reasons. 1. This way a “no-type” wire can be easily denoted, 2. this is a natural way to describe tuples of data.   To describe how much data is flowing, a star can be put next to the wire type:   Nesting – Boards and Parts If more than 5 to 10 FUs need to be put in a flow a FD starts to become hard to understand. To keep diagrams clutter free they can be nested. You can turn any FU into a flow: This leads to Flow-Designs with different levels of abstraction. A in the above illustration is a high level functional unit, A.1 and A.2 are lower level functional units. One of the purposes of Flow-Design is to be able to describe systems on different levels of abstraction and thus make it easier to understand them. Humans use abstraction/decomposition to get a grip on complexity. Flow-Design strives to support this and make levels of abstraction first class citizens for programming. You can read the above illustration like this: Functional units A.1 and A.2 detail what A is supposed to do. The whole of A´s responsibility is decomposed into smaller responsibilities A.1 and A.2. FU A thus does not do anything itself anymore! All A is responsible for is actually accomplished by the collaboration between A.1 and A.2. Since A now is not doing anything anymore except containing A.1 and A.2 functional units are devided into two categories: boards and parts. Boards are just containing other functional units; their sole responsibility is to wire them up. A is a board. Boards thus depend on the functional units nested within them. This dependency is not of a functional nature, though. Boards are not dependent on services provided by nested functional units. They are just concerned with their interface to be able to plug them together. Parts are the workhorses of flows. They contain the real domain logic. They actually transform input into output. However, they do not depend on other functional units. Please note the usage of source and sink in boards. They correspond to input-pins and output-pins of the board.   Implicit Dependencies Nesting functional units leads to a dependency tree. Boards depend on nested functional units, they are the inner nodes of the tree. Parts are independent, they are the leafs: Even though dependencies are the bane of software development, Flow-Design does not usually draw these dependencies. They are implicitly created by visually nesting functional units. And they are harmless. Boards are so simple in their functionality, they are little affected by changes in functional units they are depending on. But functional units are implicitly dependent on more than nested functional units. They are also dependent on the data types of the wires attached to them: This is also natural and thus does not need to be made explicit. And it pertains mainly to parts being dependent. Since boards don´t do anything with regard to a problem domain, they don´t care much about data types. Their infrastructural purpose just needs types of input/output-pins to match.   Explicit Dependencies You could say, Flow-Orientation is about tackling complexity at its root cause: that´s dependencies. “Natural” dependencies are depicted naturally, i.e. implicitly. And whereever possible dependencies are not even created. Functional units don´t know their collaborators within a flow. This is core to Flow-Orientation. That makes for high composability of functional units. A part is as independent of other functional units as a motor is from the rest of the car. And a board is as dependend on nested functional units as a motor is on a spark plug or a crank shaft. With Flow-Design software development moves closer to how hardware is constructed. Implicit dependencies are not enough, though. Sometimes explicit dependencies make designs easier – as counterintuitive this might sound. So FD notation needs a ways to denote explicit dependencies: Data flows along wires. But data does not flow along dependency relations. Instead dependency relations represent service calls. Functional unit C is depending on/calling services on functional unit S. If you want to be more specific, name the services next to the dependency relation: Although you should try to stay clear of explicit dependencies, they are fundamentally ok. See them as a way to add another dimension to a flow. Usually the functionality of the independent FU (“Customer repository” above) is orthogonal to the domain of the flow it is referenced by. If you like emphasize this by using different shapes for dependent and independent FUs like above. Such dependencies can be used to link in resources like databases or shared in-memory state. FUs can not only produce output but also can have side effects. A common pattern for using such explizit dependencies is to hook a GUI into a flow as the source and/or the sink of data: Which can be shortened to: Treat FUs others depend on as boards (with a special non-FD API the dependent part is connected to), but do not embed them in a flow in the diagram they are depended upon.   Attributes of Functional Units Creation and usage of functional units can be modified with attributes. So far the following have shown to be helpful: Singleton: FUs are by default multitons. FUs in the same of different flows with the same name refer to the same functionality, but to different instances. Think of functional units as objects that get instanciated anew whereever they appear in a design. Sometimes though it´s helpful to reuse the same instance of a functional unit; this is always due to valuable state it holds. Signify this by annotating the FU with a “(S)”. Multiton: FUs on which others depend are singletons by default. This is, because they usually are introduced where shared state comes into play. If you want to change them to be a singletons mark them with a “(M)”. Configurable: Some parts need to be configured before the can do they work in a flow. Annotate them with a “(C)” to have them initialized before any data items to be processed by them arrive. Do not assume any order in which FUs are configured. How such configuration is happening is an implementation detail. Entry point: In each design there needs to be a single part where “it all starts”. That´s the entry point for all processing. It´s like Program.Main() in C# programs. Mark the entry point part with an “(E)”. Quite often this will be the GUI part. How the entry point is started is an implementation detail. Just consider it the first FU to start do its job.   Patterns / Standard Parts If more than a single wire is attached to an output-pin that´s called a split (or fork). The same data is flowing on all of the wires. Remember: Flow-Designs are synchronous by default. So a split does not mean data is processed in parallel afterwards. Processing still happens synchronously and thus one branch after another. Do not assume any specific order of the processing on the different branches after the split.   It is common to do a split and let only parts of the original data flow on through the branches. This effectively means a map is needed after a split. This map can be implicit or explicit.   Although FUs can have multiple input-pins it is preferrable in most cases to combine input data from different branches using an explicit join: The default output of a join is a tuple of its input values. The default behavior of a join is to output a value whenever a new input is received. However, to produce its first output a join needs an input for all its input-pins. Other join behaviors can be: reset all inputs after an output only produce output if data arrives on certain input-pins

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  • Building a SOA/BPM/BAM Cluster Part I &ndash; Preparing the Environment

    - by antony.reynolds
    An increasing number of customers are using SOA Suite in a cluster configuration, I might hazard to say that the majority of production deployments are now using SOA clusters.  So I thought it may be useful to detail the steps in building an 11g cluster and explain a little about why things are done the way they are. In this series of posts I will explain how to build a SOA/BPM cluster using the Enterprise Deployment Guide. This post will explain the setting required to prepare the cluster for installation and configuration. Software Required The following software is required for an 11.1.1.3 SOA/BPM install. Software Version Notes Oracle Database Certified databases are listed here SOA & BPM Suites require a working database installation. Repository Creation Utility (RCU) 11.1.1.3 If upgrading an 11.1.1.2 repository then a separate script is available. Web Tier Utilities 11.1.1.3 Provides Web Server, 11.1.1.3 is an upgrade to 11.1.1.2, so 11.1.1.2 must be installed first. Web Tier Utilities 11.1.1.3 Web Server, 11.1.1.3 Patch.  You can use the 11.1.1.2 version without problems. Oracle WebLogic Server 11gR1 10.3.3 This is the host platform for 11.1.1.3 SOA/BPM Suites. SOA Suite 11.1.1.2 SOA Suite 11.1.1.3 is an upgrade to 11.1.1.2, so 11.1.1.2 must be installed first. SOA Suite 11.1.1.3 SOA Suite 11.1.1.3 patch, requires 11.1.12 to have been installed. My installation was performed on Oracle Enterprise Linux 5.4 64-bit. Database I will not cover setting up the database in this series other than to identify the database requirements.  If setting up a SOA cluster then ideally we would also be using a RAC database.  I assume that this is running on separate machines to the SOA cluster.  Section 2.1, “Database”, of the EDG covers the database configuration in detail. Settings The database should have processes set to at least 400 if running SOA/BPM and BAM. alter system set processes=400 scope=spfile Run RCU The Repository Creation Utility creates the necessary database tables for the SOA Suite.  The RCU can be run from any machine that can access the target database.  In 11g the RCU creates a number of pre-defined users and schema with a user defiend prefix.  This allows you to have multiple 11g installations in the same database. After running the RCU you need to grant some additional privileges to the soainfra user.  The soainfra user should have privileges on the transaction tables. grant select on sys.dba_pending_transactions to prefix_soainfra Grant force any transaction to prefix_soainfra Machines The cluster will be built on the following machines. EDG Name is the name used for this machine in the EDG. Notes are a description of the purpose of the machine. EDG Name Notes LB External load balancer to distribute load across and failover between web servers. WEBHOST1 Hosts a web server. WEBHOST2 Hosts a web server. SOAHOST1 Hosts SOA components. SOAHOST2 Hosts SOA components. BAMHOST1 Hosts BAM components. BAMHOST2 Hosts BAM components. Note that it is possible to collapse the BAM servers so that they run on the same machines as the SOA servers. In this case BAMHOST1 and SOAHOST1 would be the same, as would BAMHOST2 and SOAHOST2. The cluster may include more than 2 servers and in this case we add SOAHOST3, SOAHOST4 etc as needed. My cluster has WEBHOST1, SOAHOST1 and BAMHOST1 all running on a single machine. Software Components The cluster will use the following software components. EDG Name is the name used for this machine in the EDG. Type is the type of component, generally a WebLogic component. Notes are a description of the purpose of the component. EDG Name Type Notes AdminServer Admin Server Domain Admin Server WLS_WSM1 Managed Server Web Services Manager Policy Manager Server WLS_WSM2 Managed Server Web Services Manager Policy Manager Server WLS_SOA1 Managed Server SOA/BPM Managed Server WLS_SOA2 Managed Server SOA/BPM Managed Server WLS_BAM1 Managed Server BAM Managed Server running Active Data Cache WLS_BAM2 Managed Server BAM Manager Server without Active Data Cache   Node Manager Will run on all hosts with WLS servers OHS1 Web Server Oracle HTTP Server OHS2 Web Server Oracle HTTP Server LB Load Balancer Load Balancer, not part of SOA Suite The above assumes a 2 node cluster. Network Configuration The SOA cluster requires an extensive amount of network configuration.  I would recommend assigning a private sub-net (internal IP addresses such as 10.x.x.x, 192.168.x.x or 172.168.x.x) to the cluster for use by addresses that only need to be accessible to the Load Balancer or other cluster members.  Section 2.2, "Network", of the EDG covers the network configuration in detail. EDG Name is the hostname used in the EDG. IP Name is the IP address name used in the EDG. Type is the type of IP address: Fixed is fixed to a single machine. Floating is assigned to one of several machines to allow for server migration. Virtual is assigned to a load balancer and used to distribute load across several machines. Host is the host where this IP address is active.  Note for floating IP addresses a range of hosts is given. Bound By identifies which software component will use this IP address. Scope shows where this IP address needs to be resolved. Cluster scope addresses only have to be resolvable by machines in the cluster, i.e. the machines listed in the previous section.  These addresses are only used for inter-cluster communication or for access by the load balancer. Internal scope addresses Notes are comments on why that type of IP is used. EDG Name IP Name Type Host Bound By Scope Notes ADMINVHN VIP1 Floating SOAHOST1-SOAHOSTn AdminServer Cluster Admin server, must be able to migrate between SOA server machines. SOAHOST1 IP1 Fixed SOAHOST1 NodeManager, WLS_WSM1 Cluster WSM Server 1 does not require server migration. SOAHOST2 IP2 Fixed SOAHOST1 NodeManager, WLS_WSM2 Cluster WSM Server 2 does not require server migration SOAHOST1VHN VIP2 Floating SOAHOST1-SOAHOSTn WLS_SOA1 Cluster SOA server 1, must be able to migrate between SOA server machines SOAHOST2VHN VIP3 Floating SOAHOST1-SOAHOSTn WLS_SOA2 Cluster SOA server 2, must be able to migrate between SOA server machines BAMHOST1 IP4 Fixed BAMHOST1 NodeManager Cluster   BAMHOST1VHN VIP4 Floating BAMHOST1-BAMHOSTn WLS_BAM1 Cluster BAM server 1, must be able to migrate between BAM server machines BAMHOST2 IP3 Fixed BAMHOST2 NodeManager, WLS_BAM2 Cluster BAM server 2 does not require server migration WEBHOST1 IP5 Fixed WEBHOST1 OHS1 Cluster   WEBHOST2 IP6 Fixed WEBHOST2 OHS2 Cluster   soa.mycompany.com VIP5 Virtual LB LB Public External access point to SOA cluster. admin.mycompany.com VIP6 Virtual LB LB Internal Internal access to WLS console and EM soainternal.mycompany.com VIP7 Virtual LB LB Internal Internal access point to SOA cluster Floating IP addresses are IP addresses that may be re-assigned between machines in the cluster.  For example in the event of failure of SOAHOST1 then WLS_SOA1 will need to be migrated to another server.  In this case VIP2 (SOAHOST1VHN) will need to be activated on the new target machine.  Once set up the node manager will manage registration and removal of the floating IP addresses with the exception of the AdminServer floating IP address. Note that if the BAMHOSTs and SOAHOSTs are the same machine then you can obviously share the hostname and fixed IP addresses, but you still need separate floating IP addresses for the different managed servers.  The hostnames don’t have to be the ones given in the EDG, but they must be distinct in the same way as the ETC names are distinct.  If the type is a fixed IP then if the addresses are the same you can use the same hostname, for example if you collapse the soahost1, bamhost1 and webhost1 onto a single machine then you could refer to them all as HOST1 and give them the same IP address, however SOAHOST1VHN can never be the same as BAMHOST1VHN because these are floating IP addresses. Notes on DNS IP addresses that are of scope “Cluster” just need to be in the hosts file (/etc/hosts on Linux, C:\Windows\System32\drivers\etc\hosts on Windows) of all the machines in the cluster and the load balancer.  IP addresses that are of scope “Internal” need to be available on the internal DNS servers, whilst IP addresses of scope “Public” need to be available on external and internal DNS servers. Shared File System At a minimum the cluster needs shared storage for the domain configuration, XA transaction logs and JMS file stores.  It is also possible to place the software itself on a shared server.  I strongly recommend that all machines have the same file structure for their SOA installation otherwise you will experience pain!  Section 2.3, "Shared Storage and Recommended Directory Structure", of the EDG covers the shared storage recommendations in detail. The following shorthand is used for locations: ORACLE_BASE is the root of the file system used for software and configuration files. MW_HOME is the location used by the installed SOA/BPM Suite installation.  This is also used by the web server installation.  In my installation it is set to <ORACLE_BASE>/SOA11gPS2. ORACLE_HOME is the location of the Oracle SOA components or the Oracle Web components.  This directory is installed under the the MW_HOME but the name is decided by the user at installation, default values are Oracle_SOA1 and Oracle_Web1.  In my installation they are set to <MW_HOME>/Oracle_SOA and <MW_HOME>/Oracle _WEB. ORACLE_COMMON_HOME is the location of the common components and is located under the MW_HOME directory.  This is always <MW_HOME>/oracle_common. ORACLE_INSTANCE is used by the Oracle HTTP Server and/or Oracle Web Cache.  It is recommended to create it under <ORACLE_BASE>/admin.  In my installation they are set to <ORACLE_BASE>/admin/Web1, <ORACLE_BASE>/admin/Web2 and <ORACLE_BASE>/admin/WC1. WL_HOME is the WebLogic server home and is always found at <MW_HOME>/wlserver_10.3. Key file locations are shown below. Directory Notes <ORACLE_BASE>/admin/domain_name/aserver/domain_name Shared location for domain.  Used to allow admin server to manually fail over between machines.  When creating domain_name provide the aserver directory as the location for the domain. In my install this is <ORACLE_BASE>/admin/aserver/soa_domain as I only have one domain on the box. <ORACLE_BASE>/admin/domain_name/aserver/applications Shared location for deployed applications.  Needs to be provided when creating the domain. In my install this is <ORACLE_BASE>/admin/aserver/applications as I only have one domain on the box. <ORACLE_BASE>/admin/domain_name/mserver/domain_name Either unique location for each machine or can be shared between machines to simplify task of packing and unpacking domain.  This acts as the managed server configuration location.  Keeping it separate from Admin server helps to avoid problems with the managed servers messing up the Admin Server. In my install this is <ORACLE_BASE>/admin/mserver/soa_domain as I only have one domain on the box. <ORACLE_BASE>/admin/domain_name/mserver/applications Either unique location for each machine or can be shared between machines.  Holds deployed applications. In my install this is <ORACLE_BASE>/admin/mserver/applications as I only have one domain on the box. <ORACLE_BASE>/admin/domain_name/soa_cluster_name Shared directory to hold the following   dd – deployment descriptors   jms – shared JMS file stores   fadapter – shared file adapter co-ordination files   tlogs – shared transaction log files In my install this is <ORACLE_BASE>/admin/soa_cluster. <ORACLE_BASE>/admin/instance_name Local folder for web server (OHS) instance. In my install this is <ORACLE_BASE>/admin/web1 and <ORACLE_BASE>/admin/web2. I also have <ORACLE_BASE>/admin/wc1 for the Web Cache I use as a load balancer. <ORACLE_BASE>/product/fmw This can be a shared or local folder for the SOA/BPM Suite software.  I used a shared location so I only ran the installer once. In my install this is <ORACLE_BASE>/SOA11gPS2 All the shared files need to be put onto a shared storage media.  I am using NFS, but recommendation for production would be a SAN, with mirrored disks for resilience. Collapsing Environments To reduce the hardware requirements it is possible to collapse the BAMHOST, SOAHOST and WEBHOST machines onto a single physical machine.  This will require more memory but memory is a lot cheaper than additional machines.  For environments that require higher security then stay with a separate WEBHOST tier as per the EDG.  Similarly for high volume environments then keep a separate set of machines for BAM and/or Web tier as per the EDG. Notes on Dev Environments In a dev environment it is acceptable to use a a single node (non-RAC) database, but be aware that the config of the data sources is different (no need to use multi-data source in WLS).  Typically in a dev environment we will collapse the BAMHOST, SOAHOST and WEBHOST onto a single machine and use a software load balancer.  To test a cluster properly we will need at least 2 machines. For my test environment I used Oracle Web Cache as a load balancer.  I ran it on one of the SOA Suite machines and it load balanced across the Web Servers on both machines.  This was easy for me to set up and I could administer it from a web based console.

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  • Windows Azure Service Bus Scatter-Gather Implementation

    - by Alan Smith
    One of the more challenging enterprise integration patterns that developers may wish to implement is the Scatter-Gather pattern. In this article I will show the basic implementation of a scatter-gather pattern using the topic-subscription model of the windows azure service bus. I’ll be using the implementation in demos, and also as a lab in my training courses, and the pattern will also be included in the next release of my free e-book the “Windows Azure Service Bus Developer Guide”. The Scatter-Gather pattern answers the following scenario. How do you maintain the overall message flow when a message needs to be sent to multiple recipients, each of which may send a reply? Use a Scatter-Gather that broadcasts a message to multiple recipients and re-aggregates the responses back into a single message. The Enterprise Integration Patterns website provides a description of the Scatter-Gather pattern here.   The scatter-gather pattern uses a composite of the publish-subscribe channel pattern and the aggregator pattern. The publish-subscribe channel is used to broadcast messages to a number of receivers, and the aggregator is used to gather the response messages and aggregate them together to form a single message. Scatter-Gather Scenario The scenario for this scatter-gather implementation is an application that allows users to answer questions in a poll based voting scenario. A poll manager application will be used to broadcast questions to users, the users will use a voting application that will receive and display the questions and send the votes back to the poll manager. The poll manager application will receive the users’ votes and aggregate them together to display the results. The scenario should be able to scale to support a large number of users.   Scatter-Gather Implementation The diagram below shows the overall architecture for the scatter-gather implementation.       Messaging Entities Looking at the scatter-gather pattern diagram it can be seen that the topic-subscription architecture is well suited for broadcasting a message to a number of subscribers. The poll manager application can send the question messages to a topic, and each voting application can receive the question message on its own subscription. The static limit of 2,000 subscriptions per topic in the current release means that 2,000 voting applications can receive question messages and take part in voting. The vote messages can then be sent to the poll manager application using a queue. The voting applications will send their vote messages to the queue, and the poll manager will receive and process the vote messages. The questions topic and answer queue are created using the Windows Azure Developer Portal. Each instance of the voting application will create its own subscription in the questions topic when it starts, allowing the question messages to be broadcast to all subscribing voting applications. Data Contracts Two simple data contracts will be used to serialize the questions and votes as brokered messages. The code for these is shown below.   [DataContract] public class Question {     [DataMember]     public string QuestionText { get; set; } }     To keep the implementation of the voting functionality simple and focus on the pattern implementation, the users can only vote yes or no to the questions.   [DataContract] public class Vote {     [DataMember]     public string QuestionText { get; set; }       [DataMember]     public bool IsYes { get; set; } }     Poll Manager Application The poll manager application has been implemented as a simple WPF application; the user interface is shown below. A question can be entered in the text box, and sent to the topic by clicking the Add button. The topic and subscriptions used for broadcasting the messages are shown in a TreeView control. The questions that have been broadcast and the resulting votes are shown in a ListView control. When the application is started any existing subscriptions are cleared form the topic, clients are then created for the questions topic and votes queue, along with background workers for receiving and processing the vote messages, and updating the display of subscriptions.   public MainWindow() {     InitializeComponent();       // Create a new results list and data bind it.     Results = new ObservableCollection<Result>();     lsvResults.ItemsSource = Results;       // Create a token provider with the relevant credentials.     TokenProvider credentials =         TokenProvider.CreateSharedSecretTokenProvider         (AccountDetails.Name, AccountDetails.Key);       // Create a URI for the serivce bus.     Uri serviceBusUri = ServiceBusEnvironment.CreateServiceUri         ("sb", AccountDetails.Namespace, string.Empty);       // Clear out any old subscriptions.     NamespaceManager = new NamespaceManager(serviceBusUri, credentials);     IEnumerable<SubscriptionDescription> subs =         NamespaceManager.GetSubscriptions(AccountDetails.ScatterGatherTopic);     foreach (SubscriptionDescription sub in subs)     {         NamespaceManager.DeleteSubscription(sub.TopicPath, sub.Name);     }       // Create the MessagingFactory     MessagingFactory factory = MessagingFactory.Create(serviceBusUri, credentials);       // Create the topic and queue clients.     ScatterGatherTopicClient =         factory.CreateTopicClient(AccountDetails.ScatterGatherTopic);     ScatterGatherQueueClient =         factory.CreateQueueClient(AccountDetails.ScatterGatherQueue);       // Start the background worker threads.     VotesBackgroundWorker = new BackgroundWorker();     VotesBackgroundWorker.DoWork += new DoWorkEventHandler(ReceiveMessages);     VotesBackgroundWorker.RunWorkerAsync();       SubscriptionsBackgroundWorker = new BackgroundWorker();     SubscriptionsBackgroundWorker.DoWork += new DoWorkEventHandler(UpdateSubscriptions);     SubscriptionsBackgroundWorker.RunWorkerAsync(); }     When the poll manager user nters a question in the text box and clicks the Add button a question message is created and sent to the topic. This message will be broadcast to all the subscribing voting applications. An instance of the Result class is also created to keep track of the votes cast, this is then added to an observable collection named Results, which is data-bound to the ListView control.   private void btnAddQuestion_Click(object sender, RoutedEventArgs e) {     // Create a new result for recording votes.     Result result = new Result()     {         Question = txtQuestion.Text     };     Results.Add(result);       // Send the question to the topic     Question question = new Question()     {         QuestionText = result.Question     };     BrokeredMessage msg = new BrokeredMessage(question);     ScatterGatherTopicClient.Send(msg);       txtQuestion.Text = ""; }     The Results class is implemented as follows.   public class Result : INotifyPropertyChanged {     public string Question { get; set; }       private int m_YesVotes;     private int m_NoVotes;       public event PropertyChangedEventHandler PropertyChanged;       public int YesVotes     {         get { return m_YesVotes; }         set         {             m_YesVotes = value;             NotifyPropertyChanged("YesVotes");         }     }       public int NoVotes     {         get { return m_NoVotes; }         set         {             m_NoVotes = value;             NotifyPropertyChanged("NoVotes");         }     }       private void NotifyPropertyChanged(string prop)     {         if(PropertyChanged != null)         {             PropertyChanged(this, new PropertyChangedEventArgs(prop));         }     } }     The INotifyPropertyChanged interface is implemented so that changes to the number of yes and no votes will be updated in the ListView control. Receiving the vote messages from the voting applications is done asynchronously, using a background worker thread.   // This runs on a background worker. private void ReceiveMessages(object sender, DoWorkEventArgs e) {     while (true)     {         // Receive a vote message from the queue         BrokeredMessage msg = ScatterGatherQueueClient.Receive();         if (msg != null)         {             // Deserialize the message.             Vote vote = msg.GetBody<Vote>();               // Update the results.             foreach (Result result in Results)             {                 if (result.Question.Equals(vote.QuestionText))                 {                     if (vote.IsYes)                     {                         result.YesVotes++;                     }                     else                     {                         result.NoVotes++;                     }                     break;                 }             }               // Mark the message as complete.             msg.Complete();         }       } }     When a vote message is received, the result that matches the vote question is updated with the vote from the user. The message is then marked as complete. A second background thread is used to update the display of subscriptions in the TreeView, with a dispatcher used to update the user interface. // This runs on a background worker. private void UpdateSubscriptions(object sender, DoWorkEventArgs e) {     while (true)     {         // Get a list of subscriptions.         IEnumerable<SubscriptionDescription> subscriptions =             NamespaceManager.GetSubscriptions(AccountDetails.ScatterGatherTopic);           // Update the user interface.         SimpleDelegate setQuestion = delegate()         {             trvSubscriptions.Items.Clear();             TreeViewItem topicItem = new TreeViewItem()             {                 Header = AccountDetails.ScatterGatherTopic             };               foreach (SubscriptionDescription subscription in subscriptions)             {                 TreeViewItem subscriptionItem = new TreeViewItem()                 {                     Header = subscription.Name                 };                 topicItem.Items.Add(subscriptionItem);             }             trvSubscriptions.Items.Add(topicItem);               topicItem.ExpandSubtree();         };         this.Dispatcher.BeginInvoke(DispatcherPriority.Send, setQuestion);           Thread.Sleep(3000);     } }       Voting Application The voting application is implemented as another WPF application. This one is more basic, and allows the user to vote “Yes” or “No” for the questions sent by the poll manager application. The user interface for that application is shown below. When an instance of the voting application is created it will create a subscription in the questions topic using a GUID as the subscription name. The application can then receive copies of every question message that is sent to the topic. Clients for the new subscription and the votes queue are created, along with a background worker to receive the question messages. The voting application is set to receiving mode, meaning it is ready to receive a question message from the subscription.   public MainWindow() {     InitializeComponent();       // Set the mode to receiving.     IsReceiving = true;       // Create a token provider with the relevant credentials.     TokenProvider credentials =         TokenProvider.CreateSharedSecretTokenProvider         (AccountDetails.Name, AccountDetails.Key);       // Create a URI for the serivce bus.     Uri serviceBusUri = ServiceBusEnvironment.CreateServiceUri         ("sb", AccountDetails.Namespace, string.Empty);       // Create the MessagingFactory     MessagingFactory factory = MessagingFactory.Create(serviceBusUri, credentials);       // Create a subcription for this instance     NamespaceManager mgr = new NamespaceManager(serviceBusUri, credentials);     string subscriptionName = Guid.NewGuid().ToString();     mgr.CreateSubscription(AccountDetails.ScatterGatherTopic, subscriptionName);       // Create the subscription and queue clients.     ScatterGatherSubscriptionClient = factory.CreateSubscriptionClient         (AccountDetails.ScatterGatherTopic, subscriptionName);     ScatterGatherQueueClient =         factory.CreateQueueClient(AccountDetails.ScatterGatherQueue);       // Start the background worker thread.     BackgroundWorker = new BackgroundWorker();     BackgroundWorker.DoWork += new DoWorkEventHandler(ReceiveMessages);     BackgroundWorker.RunWorkerAsync(); }     I took the inspiration for creating the subscriptions in the voting application from the chat application that uses topics and subscriptions blogged by Ovais Akhter here. The method that receives the question messages runs on a background thread. If the application is in receive mode, a question message will be received from the subscription, the question will be displayed in the user interface, the voting buttons enabled, and IsReceiving set to false to prevent more questing from being received before the current one is answered.   // This runs on a background worker. private void ReceiveMessages(object sender, DoWorkEventArgs e) {     while (true)     {         if (IsReceiving)         {             // Receive a question message from the topic.             BrokeredMessage msg = ScatterGatherSubscriptionClient.Receive();             if (msg != null)             {                 // Deserialize the message.                 Question question = msg.GetBody<Question>();                   // Update the user interface.                 SimpleDelegate setQuestion = delegate()                 {                     lblQuestion.Content = question.QuestionText;                     btnYes.IsEnabled = true;                     btnNo.IsEnabled = true;                 };                 this.Dispatcher.BeginInvoke(DispatcherPriority.Send, setQuestion);                 IsReceiving = false;                   // Mark the message as complete.                 msg.Complete();             }         }         else         {             Thread.Sleep(1000);         }     } }     When the user clicks on the Yes or No button, the btnVote_Click method is called. This will create a new Vote data contract with the appropriate question and answer and send the message to the poll manager application using the votes queue. The user voting buttons are then disabled, the question text cleared, and the IsReceiving flag set to true to allow a new message to be received.   private void btnVote_Click(object sender, RoutedEventArgs e) {     // Create a new vote.     Vote vote = new Vote()     {         QuestionText = (string)lblQuestion.Content,         IsYes = ((sender as Button).Content as string).Equals("Yes")     };       // Send the vote message.     BrokeredMessage msg = new BrokeredMessage(vote);     ScatterGatherQueueClient.Send(msg);       // Update the user interface.     lblQuestion.Content = "";     btnYes.IsEnabled = false;     btnNo.IsEnabled = false;     IsReceiving = true; }     Testing the Application In order to test the application, an instance of the poll manager application is started; the user interface is shown below. As no instances of the voting application have been created there are no subscriptions present in the topic. When an instance of the voting application is created the subscription will be displayed in the poll manager. Now that a voting application is subscribing, a questing can be sent from the poll manager application. When the message is sent to the topic, the voting application will receive the message and display the question. The voter can then answer the question by clicking on the appropriate button. The results of the vote are updated in the poll manager application. When two more instances of the voting application are created, the poll manager will display the new subscriptions. More questions can then be broadcast to the voting applications. As the question messages are queued up in the subscription for each voting application, the users can answer the questions in their own time. The vote messages will be received by the poll manager application and aggregated to display the results. The screenshots of the applications part way through voting are shown below. The messages for each voting application are queued up in sequence on the voting application subscriptions, allowing the questions to be answered at different speeds by the voters.

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