Search Results

Search found 2993 results on 120 pages for 'distributed transactions'.

Page 96/120 | < Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >

• SQL Server Blocking Issue

  - by Robin Weston

  We currently have an issue that occurs roughly once a day on SQL 2005 database server, although the time it happens is not consistent. Basically, the database grinds to a halt, and starts refusing connections with the following error message. This includes logging into SSMS: A connection was successfully established with the server, but then an error occurred during the login process. (provider: TCP Provider, error: 0 - The specified network name is no longer available.) Our CPU usage for SQL is usually around 15%, but when the DB is in it's broken state it's around 70%, so it's clearly doing something, even if no-one can connect. Even if I disable the web app that uses the database the CPU still doesn't go down. I am unable to restart the SQLSERVER process as it is unresponsive, so I have to end up killing the process manually, which then puts the DB into Suspect/Recovery mode (which I can fix but it's a pain). Below are some PerfMon stats I gathered when the DB was in it's broken state which might help. I have a bunch more if people want to request them: Active Transactions: 2 (Never Changes) Logical Connections: 34 (NC) Process Blocked: 16 (NC) User Connections: 30 (NC) Batch Request: 0 (NC) Active Jobs: 2 (NC) Log Truncations: 596 (NC) Log Shrinks: 24 (NC) Longest Running Transaction Time: 99 (NC) I guess they key is finding out what the DB is using it's CPU on, but as I can't even log into SSMS this isn't possible with the standard methods. Disturbingly, I can't even use the dedicated admin connection to get into SSMS. I get the same timout as with all other requests. Any advice, reccomendations, or even sympathy, is much appreciated!

  Read the article

• Saving twice don't update my object in JDO

  - by Javi

  Hello I have an object persisted in the GAE datastore using JDO. The object looks like this: public class MyObject implements Serializable, StoreCallback { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) @Extension(vendorName="datanucleus", key="gae.encoded-pk", value="true") private String id; @Persistent private String firstId; ... } As usually when the object is stored for the first time a new id value is generated for the identifier. I need that if I don't provide a value for firstId it sets the same value as the id. I don't want to solve it with a special getter which checks for null value in firstId and then return the id value because I want to make queries relating on firstId. I can do it in this way by saving the object twice (Probably there's a better way to do this, but I'll do it in this way until I find a better one). But it is not working. when I debug it I can see that result.firstId is set with the id value and it seems to be persisted, but when I go into the datastore I see that firstId is null (as it was saved the first time). This save method is in my DAO and it is called in another save method in the service annotated with @Transactional. Does anyone have any idea why the second object in not persisted properly? @Override public MyObject save(MyObject obj) { PersistenceManager pm = JDOHelper.getPersistenceManagerFactory("transactions-optional"); MyObject result = pm.makePersistent(obj); if(result.getFirstId() == null){ result.setFirstId(result.getId()); result = pm.makePersistent(result); } return result; } Thanks.

  Read the article

• What issues to consider when rolling your own data-backend for Silverlight / AJAX on non-ASP.NET ser

  - by Edward Tanguay

  I have read-only Silverlight and AJAX apps which read static text and XML files from a PHP/Apache server, which works very nicely with features such as asynchronous loading, lazy-loading only what I need for each page, loading in the background, developed a little query language to get a PHP script to create custom XML files etc. it's pragmatic read-only REST, and all works fast and fine for read-only sites. Now I want to also add the ability to write data from these apps to a database on the same PHP/Apache server. For those of you who have built similar data-access layers, what do I need to consider while building this, especially regarding security so that not just any client can write and alter my database, e.g.: check HTTP_USER_AGENT for security check REMOTE_ADDR for security require a special code for security, perhaps a list of TAN codes (such as banks use for online transactions) each which can only be used once, both the client and server have these I wonder if there is some kind of standard REST query I should lean on for e.g. building SQL-like statements in the URL parameters, e.g. http://www.thedatalayersite.com/query?insertinto=customers&... Any thoughts, notes from experience, ideas, gotchas, especially ideas on tightening down security in this endeavor would be helpful.

  Read the article

• How do I test database-related code with NUnit?

  - by Michael Haren

  I want to write unit tests with NUnit that hit the database. I'd like to have the database in a consistent state for each test. I thought transactions would allow me to "undo" each test so I searched around and found several articles from 2004-05 on the topic: http://weblogs.asp.net/rosherove/archive/2004/07/12/180189.aspx http://weblogs.asp.net/rosherove/archive/2004/10/05/238201.aspx http://davidhayden.com/blog/dave/archive/2004/07/12/365.aspx http://haacked.com/archive/2005/12/28/11377.aspx These seem to resolve around implementing a custom attribute for NUnit which builds in the ability to rollback DB operations after each test executes. That's great but... Does this functionality exists somewhere in NUnit natively? Has this technique been improved upon in the last 4 years? Is this still the best way to test database-related code? Edit: it's not that I want to test my DAL specifically, it's more that I want to test pieces of my code that interact with the database. For these tests to be "no-touch" and repeatable, it'd be awesome if I could reset the database after each one. Further, I want to ease this into an existing project that has no testing place at the moment. For that reason, I can't practically script up a database and data from scratch for each test.

  Read the article

• Zend: Fetching row from session db table after generating session id

  - by Nux

  Hi, I'm trying to update the session table used by Zend_Session_SaveHandler_DbTable directly after authenticating the user and writing the session to the DB. But I can neither update nor fetch the newly inserted row, even though the session id I use to check (Zend_Session::getId()) is valid and the row is indeed inserted into the table. Upon fetching all session ids (on the same request) the one I newly inserted is missing from the results. It does appear in the results if I fetch it with something else. I've checked whether it is a problem with transactions and that does not seem to be the problem - there is no active transaction when I'm fetching the results. I've also tried fetching a few seconds after writing using sleep(), which doesn't help. $auth->getStorage()->write($ident); //sleep(1) $update = $this->db->update('session', array('uid' => $ident->user_id), 'id='.$this->db->quote(Zend_Session::getId())); $qload = 'SELECT id FROM session'; $load = $this->db->fetchAll($qload); echo $qload; print_r($load); $update fails. $load doesn't contain the row that was written with $auth-getStorage()-write($identity). $qload does contain the correct query - copying it to somewhere else leads to the expected result, that is the inserted row is included in the results. Database used is MySQL - InnoDB. If someone knows how to directly fix this (i.e. on the same request, not doing something like updating after redirecting to another page) without modifying Zend_Session_SaveHandler_DbTable: Thank you very much!

  Read the article

• Embedded non-relational (nosql) data store

  - by Igor Brejc

  I'm thinking about using/implementing some kind of an embedded key-value (or document) store for my Windows desktop application. I want to be able to store various types of data (GPS tracks would be one example) and of course be able to query this data. The amount of data would be such that it couldn't all be loaded into memory at the same time. I'm thinking about using sqlite as a storage engine for a key-value store, something like y-serial, but written in .NET. I've also read about FriendFeed's usage of MySQL to store schema-less data, which is a good pointer on how to use RDBMS for non-relational data. sqlite seems to be a good option because of its simplicity, portability and library size. My question is whether there are any other options for an embedded non-relational store? It doesn't need to be distributable and it doesn't have to support transactions, but it does have to be accessible from .NET and it should have a small download size. UPDATE: I've found an article titled SQLite as a Key-Value Database which compares sqlite with Berkeley DB, which is an embedded key-value store library.

  Read the article

• Reasons for & against a Database

  - by dbemerlin

  Hi, i had a discussion with a coworker about the architecture of a program i'm writing and i'd like some more opinions. The Situation: The Program should update at near-realtime (+/- 1 Minute). It involves the movement of objects on a coordinate system. There are some events that occur at regular intervals (i.e. creation of the objects). Movements can change at any time through user input. My solution was: Build a server that runs continously and stores the data internally. The server dumps a state-of-the-program at regular intervals to protect against powerfailures and/or crashes. He argued that the program requires a Database and i should use cronjobs to update the data. I can store movement information by storing startpoint, endpoint and speed and update the position in the cronjob (and calculate collisions with other objects there) by calculating direction and speed. His reasons: Requires more CPU & Memory because it runs constantly. Powerfailures/Crashes might destroy data. Databases are faster. My reasons against this are mostly: Not very precise as events can only occur at full minutes (wouldn't be that bad though). Requires (possibly costly) transformation of data on every run from relational data to objects. RDBMS are a general solution for a specialized problem so a specialized solution should be more efficient. Powerfailures (or other crashes) can leave the Data in an undefined state with only partially updated data unless (possibly costly) precautions (like transactions) are taken. What are your opinions about that? Which arguments can you add for any side?

  Read the article

• Return if remote stored procedure fails

  - by njk

  I am in the process of creating a stored procedure. This stored procedure runs local as well as external stored procedures. For simplicity, I'll call the local server [LOCAL] and the remote server [REMOTE]. USE [LOCAL] GO SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO ALTER PROCEDURE [dbo].[monthlyRollUp] AS SET NOCOUNT, XACT_ABORT ON BEGIN TRY EXEC [REOMTE].[DB].[table].[sp] --This transaction should only begin if the remote procedure does not fail BEGIN TRAN EXEC [LOCAL].[DB].[table].[sp1] COMMIT BEGIN TRAN EXEC [LOCAL].[DB].[table].[sp2] COMMIT BEGIN TRAN EXEC [LOCAL].[DB].[table].[sp3] COMMIT BEGIN TRAN EXEC [LOCAL].[DB].[table].[sp4] COMMIT END TRY BEGIN CATCH -- Insert error into log table INSERT INTO [dbo].[log_table] (stamp, errorNumber, errorSeverity, errorState, errorProcedure, errorLine, errorMessage) SELECT GETDATE(), ERROR_NUMBER(), ERROR_SEVERITY(), ERROR_STATE(), ERROR_PROCEDURE(), ERROR_LINE(), ERROR_MESSAGE() END CATCH GO When using a transaction on the remote procedure, it throws this error: OLE DB provider ... returned message "The partner transaction manager has disabled its support for remote/network transactions.". I get that I'm unable to run a transaction locally for a remote procedure. How can I ensure that the this procedure will exit and rollback if any part of the procedure fails?

  Read the article

• Re-use of database object in sub-sonic

  - by cantabilesoftware

  Yet another newbie SubSonic/ActiveRecord question. Suppose I want to insert a couple of records, currently I'm doing this: using (var scope = new System.Transactions.TransactionScope()) { // Insert company company c = new company(); c.name = "ACME"; c.Save(); // Insert some options company_option o = new company_option(); o.name = "ColorScheme"; o.value = "Red"; o.company_id = c.company_id; o.Save(); o = new company_option(); o.name = "PreferredMode"; o.value = "Fast"; o.company_id = c.company_id; o.Save(); scope.Complete(); } Stepping through this code however, each of the company/company_option constructors go off and create a new myappDB object which just seems wasteful. Is this the recommended approach or should I be trying to re-use a single DB object - and if so, what's the easiest way to do this?

  Read the article

• Practiaal rules for Django MiddleWare ordering?

  - by o_O Tync

  The official documentation is a bit messy: 'before' & 'after' are used for ordering MiddleWare in a tuple, but in some places 'before'&'after' refers to request-response phases. Also, 'should be first/last' are mixed and it's not clear which one to use as 'first'. I do understand the difference.. however it seems to complicated for a newbie in Django. Can you suggest some correct ordering for builtin MiddleWare classes (assuming we enable all of them) and — most importantly — explain WHY one goes before/after other ones? here's the list, with the info from docs I managed to find: UpdateCacheMiddleware Before those that modify 'Vary:' SessionMiddleware, GZipMiddleware, LocaleMiddleware GZipMiddleware Before any MW that may change or use the response body After UpdateCacheMiddleware: Modifies 'Vary:' ConditionalGetMiddleware Before CommonMiddleware: uses its 'Etag:' header when USE_ETAGS=True SessionMiddleware After UpdateCacheMiddleware: Modifies 'Vary:' Before TransactionMiddleware: we don't need transactions here LocaleMiddleware, One of the topmost, after SessionMiddleware, CacheMiddleware After UpdateCacheMiddleware: Modifies 'Vary:' After SessionMiddleware: uses session data CommonMiddleware Before any MW that may change the response (it calculates ETags) After GZipMiddleware so it won't calculate an E-Tag on gzipped contents Close to the top: it redirects when APPEND_SLASH or PREPEND_WWW CsrfViewMiddleware AuthenticationMiddleware After SessionMiddleware: uses session storage MessageMiddleware After SessionMiddleware: can use Session-based storage XViewMiddleware TransactionMiddleware After MWs that use DB: SessionMiddleware (configurable to use DB) All *CacheMiddleWare is not affected (as an exception: uses own DB cursor) FetchFromCacheMiddleware After those those that modify 'Vary:' if uses them to pick a value for cache hash-key After AuthenticationMiddleware so it's possible to use CACHE_MIDDLEWARE_ANONYMOUS_ONLY FlatpageFallbackMiddleware Bottom: last resort Uses DB, however, is not a problem for TransactionMiddleware (yes?) RedirectFallbackMiddleware Bottom: last resort Uses DB, however, is not a problem for TransactionMiddleware (yes?) (I will add suggestions to this list to collect all of them in one place)

  Read the article

• What's the most DRY-appropriate way to execute an SQL command?

  - by Sean U

  I'm looking to figure out the best way to execute a database query using the least amount of boilerplate code. The method suggested in the SqlCommand documentation: private static void ReadOrderData(string connectionString) { string queryString = "SELECT OrderID, CustomerID FROM dbo.Orders;"; using (SqlConnection connection = new SqlConnection(connectionString)) { SqlCommand command = new SqlCommand(queryString, connection); connection.Open(); SqlDataReader reader = command.ExecuteReader(); try { while (reader.Read()) { Console.WriteLine(String.Format("{0}, {1}", reader[0], reader[1])); } } finally { reader.Close(); } } } mostly consists of code that would have to be repeated in every method that interacts with the database. I'm already in the habit of factoring out the establishment of a connection, which would yield code more like the following. (I'm also modifying it so that it returns data, in order to make the example a bit less trivial.) private SQLConnection CreateConnection() { var connection = new SqlConnection(_connectionString); connection.Open(); return connection; } private List<int> ReadOrderData() { using(var connection = CreateConnection()) using(var command = connection.CreateCommand()) { command.CommandText = "SELECT OrderID FROM dbo.Orders;"; using(var reader = command.ExecuteReader()) { var results = new List<int>(); while(reader.Read()) results.Add(reader.GetInt32(0)); return results; } } } That's an improvement, but there's still enough boilerplate to nag at me. Can this be reduced further? In particular, I'd like to do something about the first two lines of the procedure. I don't feel like the method should be in charge of creating the SqlCommand. It's a tiny piece of repetition as it is in the example, but it seems to grow if transactions are being managed manually or timeouts are being altered or anything like that.

  Read the article

• SQL Server becomes slow after restart

  - by Tobi DM

  We use SQL Server 2005 on an Windwos Server 2008. Ther Server has 48 GB RAM. SQL Server is configured to use 40 GB RAM. There is only one database hosted (About 70 GB). The only app beside SQL Server is our App-Server which connects the clients to the database. Now we encounter the following problem: After a restart of the server our the performance is great. The server grabs the 40 GB RAM wich it is allowed to and then runs fast as hell. But after about 4 weeks the system becomes slower and slower. The execution of statements (seen in the profiler) is raising slowly. But I cannot see that there is something going wrong on the server. CPU usage is at about 20% I/O also seems to be no Problem The process monitor does also not show that there are strange apps or something like that. Eventlog does also have no interessting messages No open transactions or blockings to see We tried already the following things without effect: Droped the cache by using the statements DBCC FreeProcCache DBCC FREESYSTEMCACHE('ALL') DBCC DropCleanbuffers Restarted the Appserver we are using. Restart the sql server service But nothing did help exept restarting the whole server. Any ideas?

  Read the article

• calculating offer period for subscription

  - by TheVillageIdiot

  I'm maintaining a web application which deals with some kind of subscriptions. Users can to renew their subscriptions from 2 months before expiry (not earlier than that). Sometimes user does not renew before expiry and get grace period which is of 3 months. Now he can renew in these 3 months of grace period. Now the problem part. In the previous transactions of renew requests I have to show what was the offer period for that particular request (subscription start and subscription end period if renew was granted). Things are pretty simple if user renews before expiry, but I'm not able to get things straight if there is grace period specially when the subscriptions is expiring in last months of the year. Also there sometimes calculations go haywire when subscription is ending in jan or feb. All this is happening because offer period is not saved with the application anywhere (I don't know why). so if subscription is ending in 20 October 2008 and renew application is submitted in 16 January 2009 (because of grace period) the offer period should be 21 October 2008 to 20 October 2009.

  Read the article

• Putting Select Statement on Hibernate Transaction

  - by Mark Estrada

  Hi All, I have been reading the net for a while regarding Hibernate but I can seem to understand one concept regarding Transaction. On some site that I have visit, Select statements are in transaction mode like this. public List<Book> readAll() { Session session = HibernateUtil.getSessionFactory() .getCurrentSession(); session.beginTransaction(); List<Book> booksList = session.createQuery("from Book").list(); session.getTransaction().commit(); return booksList; } While on some site, it does not advocate the use of transaction on Select statements public List<Book> readAll() { Session session = HibernateUtil.getSessionFactory() .getCurrentSession(); List<Book> booksList = session.createQuery("from Book").list(); return booksList; } I am thinking which one should I follow. Any thoughts please? Are transactions needed on Select Statements or not? Thanks

  Read the article

• Referencing object's identity before submitting changes in LINQ

  - by Axarydax

  Hi, is there a way of knowing ID of identity column of record inserted via InsertOnSubmit beforehand, e.g. before calling datasource's SubmitChanges? Imagine I'm populating some kind of hierarchy in the database, but I wouldn't want to submit changes on each recursive call of each child node (e.g. if I had Directories table and Files table and am recreating my filesystem structure in the database). I'd like to do it that way, so I create a Directory object, set its name and attributes, then InsertOnSubmit it into DataContext.Directories collection, then reference Directory.ID in its child Files. Currently I need to call InsertOnSubmit to insert the 'directory' into the database and the database mapping fills its ID column. But this creates a lot of transactions and accesses to database and I imagine that if I did this inserting in a batch, the performance would be better. What I'd like to do is to somehow use Directory.ID before commiting changes, create all my File and Directory objects in advance and then do a big submit that puts all stuff into database. I'm also open to solving this problem via a stored procedure, I assume the performance would be even better if all operations would be done directly in the database.

  Read the article

• SQL2008 merge replication fails to update depdendent items when table is added

  - by Dan Puzey

  Setup: an existing SQL2008 merge replication scenario. A large server database, including views and stored procs, being replicated to client machines. What I'm doing: * adding a new table to the database * mark the new table for replication (using SP_AddMergeArticle) * alter a view (which is already part of the replicated content) is updated to include fields from this new table (which is joined to the tables in the existing view). A stored procedure is similarly updated. The problem: the table gets replicated to client machines, but the view is not updated. The stored procedure is also not updated. Non-useful workaround: if I run the snapshot agent after calling SP_AddMergeArticle and before updating the view/SP, both the view and the stored procedure changes correctly replicate to the client. The bigger problem: I'm running a list of database scripts in a transaction, as part of a larger process. The snapshot agent can't be run during a transaction, and if I interrupt the transaction (e.g. by running the scripts in multiple transactions), I lose the ability to roll back the changes should something fail. Does anyone have any suggestions? It seems like I must be missing something obvious, because I don't see why the changes to the view/sproc wouldn't be replicating anyway, regardless of what's going on with the new table.

  Read the article

• Messages not forwarded to error queue when exception is thrown in handler (it works on my machine)

  - by darthjit

  e are using NServicebus 4.0.5 with sql server(sql server 2012) as transport. When the handler throws an exception, NSB does not retry or move the message to the error queue. Successful messages make it to the audit queue but the failed/errored ones don't! . Interestingly, all this works on our local machines(windows 7 ,sql server localdb) but not on windows server 2012 (sql server 2012). Here is the config info on the subscriber: <add name="NServiceBus/Transport" connectionString="Data Source=xxx;Initial Catalog=NServiceBus;Integrated Security=SSPI;Enlist=false;" /> <add name="NServiceBus/Persistence" connectionString="Data Source=xxx;Initial Catalog=NServiceBus;Integrated Security=SSPI;Enlist=false;" /> <MessageForwardingInCaseOfFaultConfig ErrorQueue="error" /> <UnicastBusConfig ForwardReceivedMessagesTo="audit"> <MessageEndpointMappings> <add Assembly="Services.Section.Messages" Endpoint= "Services.ACL.Worker" /> </MessageEndpointMappings> </UnicastBusConfig> And in code it is configured as follows: public class EndpointConfig : IConfigureThisEndpoint, AsA_Server, IWantCustomInitialization { public void Init() { IContainer container = ContainerInstanceProvider. GetContainerInstance(); Configure .Transactions.Enable(); Configure.With() .AutofacBuilder(container) .UseTransport<SqlServer>() .Log4Net() //.Serialization.Json() .UseNHibernateSubscriptionPersister() .UseNHibernateTimeoutPersister() .MessageForwardingInCaseOfFault() .RijndaelEncryptionService() .DefiningCommandsAs(type => type.Namespace != null &&type .Namespace.EndsWith("Commands")) .DefiningEventsAs(type => type.Namespace != null &&type .Namespace.EndsWith("Events")) .UnicastBus(); } } Any ideas on how to fix this? here is the log info (there is a lot there, search for error to see the relevant parts) https://gist.github.com/ranji/7378249

  Read the article

• Rolling back file moves, folder deletes and mysql queries

  - by Workoholic

  This has been bugging me all day and there is no end in sight. When the user of my php application adds a new update and something goes wrong, I need to be able to undo a complex batch of mixed commands. They can be mysql update and insert queries, file deletes and folder renaming and creations. I can track the status of all insert commands and undo them if an error is thrown. But how do I do this with the update statements? Is there a smart way (some design pattern?) to keep track of such changes both in the file structure and the database? My database tables are MyISAM. It would be easy to just convert everything to InnoDB, so that I can use transactions. That way I would only have to deal with the file and folder operations. Unfortunately, I cannot assume that all clients have InnoDB support. It would also require me to convert many tables in my database to InnoDB, which I am hesitant to do.

  Read the article

• MySQL Connector: parameters not being added

  - by LookitsPuck

  Hey all! Looking at my query log for MySQL, I see my parameters aren't being added. Here's my code: MySqlConnection conn = new MySqlConnection(ApplicationVariables.ConnectionString()); MySqlCommand com = new MySqlCommand(); try { conn.Open(); com.Connection = conn; com.CommandText = String.Format(@"SELECT COUNT(*) AS totalViews FROM pr_postreleaseviewslog AS prvl WHERE prvl.dateCreated BETWEEN (@startDate) AND (@endDate) AND prvl.postreleaseID IN ({0})" , ids); com.CommandType = CommandType.Text; com.Parameters.Add(new MySqlParameter("@startDate", thisCampaign.Startdate)); com.Parameters.Add(new MySqlParameter("@endDate", endDate)); numViews = Convert.ToInt32(com.ExecuteScalar()); } catch (Exception ex) { } finally { conn.Dispose(); com.Dispose(); } Looking at the query log, I see this: SELECT COUNT(*) AS totalViews FROM pr_postreleaseviewslog AS prvl WHERE prvl.dateCreated BETWEEN (@startDate) AND (@endDate) AND prvl.postreleaseID IN (1,2) I've used the MySQL .NET connector on countless projects (I actually have a base class that takes care of opening these connections, and closing them with transactions, etc.). However, I took over this application, and here I am now. Thanks for the help!

  Read the article

• django class with an array of "parent" foreignkeys issue

  - by user298032

  Let's say I have a class called Fruit with child classes of the different kinds of Fruit with their own specific attributes, and I want to collect them in a FruitBasket: class Fruit(models.Model):     type = models.CharField(max_length=120,default='banana',choices=FRUIT_TYPES)     ... class Banana(Fruit):     """banana (fruit type)"""     length = models.IntegerField(blank=True, null=True)     ... class Orange(Fruit):     """orange (fruit type)"""     diameter = models.IntegerField(blank=True, null=True)     ... class FruitBasket(models.Model):     fruits = models.ManyToManyField(Fruit)     ... The problem I seem to be having is when I retrieve and inspect the Fruits in a FruitBasket, I only retrieve the Fruit base class and can't get at the Fruit child class attributes. I think I understand what is happening--when the array is retrieved from the database, the only fields that are retrieved are the Fruit base class fields. But is there some way to get the child class attributes as well without multiple expensive database transactions? (For example, I could get the array, then retrieve the child Fruit classes by the id of each array element). thanks in advance, Chuck

  Read the article

• Working with complex objects in Prevayler commands

  - by alexantd

  The demos included in the Prevayler distribution show how to pass in a couple strings (or something simple like that) into a command constructor in order to create or update an object. The problem is that I have an object called MyObject that has a lot of fields. If I had to pass all of them into the CreateMyObject command manually, it would be a pain. So an alternative I thought of is to pass my business object itself into the command, but to hang onto a clone of it (keeping in mind that I can't store the BO directly in the command). Of course after executing this command, I would need to make sure to dispose of the original copy that I passed in. public class CreateMyObject implements TransactionWithQuery { private MyObject object; public CreateMyObject(MyObject business_obj) { this.object = (MyObject) business_obj.clone(); } public Object executeAndQuery(...) throws Exception { ... } } The Prevayler wiki says: Transactions can't carry direct object references (pointers) to business objects. This has become known as the baptism problem because it's a common beginner pitfall. Direct object references don't work because once a transaction has been serialized to the journal and then deserialized for execution its object references no longer refer to the intended objects - - any objects they may have referred to at first will have been copied by the serialization process! Therefore, a transaction must carry some kind of string or numeric identifiers for any objects it wants to refer to, and it must look up the objects when it is executed. I think by cloning the passed-in object I will be getting around the "direct object pointer" problem, but I still don't know whether or not this is a good idea...

  Read the article

• What arguments to use to explain why a SQL DB is far better then a flat file

  - by jamone

  The higher ups in my company were told by good friends that flat files are the way to go, and we should switch from MS SQL server to them for everything we do. We have over 300 servers and hundreds of different databases. From just the few I'm involved with we have 10 billion records in quite a few of them with upwards of 100k new records a day and who knows how many updates... Me and a couple others need to come up with a response saying why we shouldn't do this. Most of our stuff is ASP.NET with some legacy ASP. We thought that making a simple console app that tests/times the same interactions between a flat file (stored on the network) and SQL over the network doing large inserts, searches, updates etc along with things like network disconnects randomly. This would show them how bad flat files can be espically when you are dealing with millions of records. What things should I use in my response? What should I do with my demo code to illustrate this? My sort list so far: Security Concurent access Performance with large ammounts of data Ammount of time to do such a massive rewrite/switch Lack of transactions PITA to map relational data to flat files I fear that this will be a great post on the Daily WTF someday if I can't stop it now.

  Read the article

• Have I found a security problem in an API or do I just not understand SSL?

  - by jamieb

  I'm working on building a set of Python bindings around an XML-based API provided by a vendor. The vendor requires that all transactions be conducted over SSL. Using a Linux box, I created a key file and a CSR for my application. Using their self-service web portal, I then generate a certificate using that CSR. Both the key file and the certificate are used when making the SSL request to the API. I'm now working on designing exception classes to make error messages more verbose (and, hopefully, more useful to developers using my bindings). Part of my testing has included altering the key file: transpose a couple characters here, replace 4 or 5 with random characters there, etc. To my surprise, altering the key file had no effect! As long as I didn't change the total length of it, the API didn't complain about a bad key file. The only way I was able to throw an error was by swapping in a completely different key from another application. At that point, the API complained about the Common Name not matching. Is this normal behavior or has the vendor not properly implemented SSL?

  Read the article

• Creating a function in Postgresql that does not return composite values

  - by celenius

  I'm learning how to write functions in Postgresql. I've defined a function called _tmp_myfunction() which takes in an id and returns a table (I also define a table object type called _tmp_mytable) -- create object type to be returned CREATE TYPE _tmp_mytable AS ( id integer, cost double precision ); -- create function which returns query CREATE OR REPLACE FUNCTION _tmp_myfunction( id integer ) RETURNS SETOF _tmp_mytable AS $$ BEGIN RETURN QUERY SELECT id, cost FROM sales WHERE id = sales.id; END; $$ LANGUAGE plpgsql; This works fine when I use one id and call it using the following approach: SELECT * FROM _tmp_myfunction(402); What I would like to be able to do is to call it, but to use a column of values instead of just one value. However, if I use the following approach I end up with all values of the table in one column, separated by commas: -- call function using all values in a column SELECT _tmp_myfunction(t.id) FROM transactions as t; I understand that I can get the same result if I use SELECT _tmp_myfunction(402); instead of SELECT * FROM _tmp_myfunction(402); but I don't know how to construct my query in such a way that I can separate out the results.

  Read the article

• Atomically maintaining a counter using Sub-sonic ActiveRecord

  - by cantabilesoftware

  I'm trying to figure out the correct way to atomically increment a counter in one table and use that incremented value as an pseudo display-only ID for a record in another. What I have is a companies table and a jobs table. I want each company to have it's own set of job_numbers. I do have an auto increment job_id, but those numbers are shared across all companies. ie: the job numbers should generally increment without gaps for each company. ie: companies(company_id, next_job_number) jobs(company_id, job_id, job_number) Currently I'm doing this (as a method on the partial job class): public void SaveJob() { using (var scope = new System.Transactions.TransactionScope()) { if (job_id == 0) { _db.Update<company>() .SetExpression("next_job_number").EqualTo("next_job_number+1") .Where<company>(x => x.company_id == company_id) .Execute(); company c = _db.companies.SingleOrDefault(x => x.company_id == company_id); job_number = c.next_job_number; } // Save the job this.Save(); scope.Complete(); } } It seems to work, but I'm not sure if there are pitfalls here? It just feels wrong, but I'm not sure how else to do it. Any advice appreciated.

  Read the article

< Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >