Search Results

Search found 67143 results on 2686 pages for 'complex data types'.

Page 463/2686 | < Previous Page | 459 460 461 462 463 464 465 466 467 468 469 470  | Next Page >

  • Is there a way to reliably backup and restore a complex network configuration on Windows XP?

    - by djangofan
    I have some Windows XP laptops (10+) that host a ad-hoc WIFI network connection to wireless PDA devices. The laptop itself is connected via a 3rd party VPN radio network. The radio network itself seems to be reliable. If one small thing goes wrong with the network configuration then the PDA loses connectivity and so I need a way to backup a networking config , either via a script or a 3rd party program, so that I can restore a working network configuration if something goes wrong. Is this possible? Does anyone have any ideas?

    Read the article

  • "Test to measure your ability to follow directions and solve complex problems in a neat and orderly manner." [closed]

    - by Matt
    Use the table of symbol substitutions when answering the problem below: Circle = 0 Dot = 1 Line = 2 Triangle = 3 Square = 4 Pentagon = 5 Hexagon = 6 Cross = 7 Heart = 8 Smiley Face = 9 Use the following special rule when answering the problem below: If ever a square is next to a cross during long multiplication, the square shall be treated as a triangle. Problem: Show your work in doing long multiplication of Pentagon Pentagon Nonagon by Line Square Octagon. Show your work using symbols not numbers.

    Read the article

  • Facebook sort Presto, son moteur de requêtes open source pour le big data, qui serait dix fois plus performant que celui de Hadoop

    Facebook sort Presto, son moteur de requêtes open source pour le big data qui serait dix fois plus performant que celui de HadoopDe nombreuses entreprises comme Facebook dépendent du Big data. Dans le domaine, on compte la paire Hadoop/Hive parmi les références. Pour rappel, Hive c'est le moteur de requêtes populaire pour Hadoop. Cependant, il se pourrait que le MapReduce élément essentiel sur lequel repose Hive ne soit pas optimisé pour des situations ou la quantité de données excède un certain...

    Read the article

  • Windows Server 2003 - Are ODBC Data Source's set per-user?

    - by Jakobud
    When I'm logged into our Windows Server 2003 server, I don't see any ODBC Data Sources, but when a different user logs in (who doesn't have Administrative rights), they have a big list of ODBC Data Sources. Are ODBC Data Sources set on a per-user basis? How come the Administrator can't see user's ODBC Data Sources?

    Read the article

  • Les Bouches-du-Rhône sponsorisent des développeurs pour promouvoir l'open data : avez-vous proposé votre application ?

    Les Bouches-du-Rhône lancent une opération de sponsoring pour les développeurs d'applications et de sites web Afin de promouvoir l'open-data et la région, Developpez.com partenaire Depuis le mois d'avril, l'association Bouches-du-Rhône Tourisme a rejoint la démarche Open-data en ouvrant son portail et en libérant une centaine de jeux de données liées au tourisme dans le département. Toutes les informations détenues par l'association ont été rendues disponibles et exploitables par les développeurs, les scientifiques, les associations, les étudiants et les entreprises. Bref, par tout le monde. On y trouve par exemple...

    Read the article

  • Les Bouches-du-Rhône lancent une opération de sponsoring de développeurs pour promouvoir l'open-data et la région

    Les Bouches-du-Rhône lancent une opération de sponsoring pour les développeurs d'applications et de sites web Afin de promouvoir l'open-data et la région, Developpez.com partenaire Depuis le mois d'avril, l'association Bouches-du-Rhône Tourisme a rejoint la démarche Open-data en ouvrant son portail et en libérant une centaine de jeux de données liées au tourisme dans le département. Toutes les informations détenues par l'association ont été rendues disponibles et exploitables par les développeurs, les scientifiques, les associations, les étudiants et les entreprises. Bref, par tout le monde. On y trouve par...

    Read the article

  • How can I tell the Data Annotations validator to also validate complex child properties?

    - by GWB
    Can I automatically validate complex child objects when validating a parent object and include the results in the populated ICollection<ValidationResult>? If I run the following code: using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; namespace ConsoleApplication1 { public class Person { [Required] public string Name { get; set; } public Address Address { get; set; } } public class Address { [Required] public string Street { get; set; } [Required] public string City { get; set; } [Required] public string State { get; set; } } class Program { static void Main(string[] args) { Person person = new Person { Name = null, Address = new Address { Street = "123 Any St", City = "New York", State = null } }; var validationContext = new ValidationContext(person, null, null); var validationResults = new List<ValidationResult>(); var isValid = Validator.TryValidateObject(person, validationContext, validationResults); Console.WriteLine(isValid); validationResults.ForEach(r => Console.WriteLine(r.ErrorMessage)); Console.ReadKey(true); } } } I get the following output: False The Name field is required. But I was expecting something similar to: False The Name field is required. The State field is required.

    Read the article

  • Need help with creating complex UITableView items (like the Settings app).

    - by Craig
    I hoping to create a custom Settings view, similar to the Settings application, but with more control over the UI and access to some settings (i need to lock some of the settings). Obvously, there are a variety of UI elements mixed in each row of application's UITableView. For example, the 'Airplane Mode' setting shows a UISwitch, while the 'Wi-Fi' setting has a text value adjacent to the disclosure symbol (''). Further complicating matters, is the grouping of these settings. I have some general questions about the approach I should take: Seems like i need to save the name of the setting, its current value, its grouping, and the type of UI element(s) needed to modify its value. i would like to make use [NSUserDefault standardUserDefaults], but not have these settings appear in the Settings application. I'm guessing that I will need to create my own settings-persistence class. is it better to build each one of these complex UI-element combinations in code or to create a series of custom views based on the UITableViewCell and load the appropriate one? i'm guessing the latter. some of the setting require that i load another view to select its value. assuming that the application is based on the Utility pattern, should the SettingsView manage the navigation stack, rather than having the app delegate do so? Thanks for your time and comments. Craig Buchanan

    Read the article

  • Should I be relying on WebTests for data validation?

    - by Alexander Kahoun
    I have a suite of web tests created for a web service. I use it for testing a particular input method that updates a SQL Database. The web service doesn't have a way to retrieve the data, that's not its purpose, only to update it. I have a validator that validates the response XML that the web service generates for each request. All that works fine. It was suggested by a teammate that I add data validation so that I check the database to see the data after the initial response validator runs and compare it with what was in the input request. We have a number of services and libraries that are separate from the web service I'm testing that I can use to get the data and compare it. The problem is that when I run the web test the data validation always fails even when the request succeeds. I've tried putting the thread to sleep between the response validation and the data validation but to no avail; It always gets the data from before the response validation. I can set a break point and visually see that the data has been updated in the DB, funny thing is when I step through it in debug with the breakpoint it does validate successfully. Before I get too much more into this issue I have to ask; Is this the purpose of web tests? Should I be able to validate data through service calls in this manner or am I asking too much of a web test and the response validation is as far as I should go?

    Read the article

  • Am I correctly extracting JPEG binary data from this mysqldump?

    - by Glenn
    I have a very old .sql backup of a vbulletin site that I ran around 8 years ago. I am trying to see the file attachments that are stored in the DB. The script below extracts them all and is verified to be JPEG by hex dumping and checking the SOI (start of image) and EOI (end of image) bytes (FFD8 and FFD9, respectively) according to the JPEG wiki page. But when I try to open them with evince, I get this message "Error interpreting JPEG image file (JPEG datastream contains no image)" What could be going on here? Some background info: sqldump is around 8 years old vbulletin 2.x was the software that stored the info most likely php 4 was used most likely mysql 4.0, possibly even 3.x the column datatype these attachments are stored in is mediumtext My Python 3.1 script: #!/usr/bin/env python3.1 import re trim_l = re.compile(b"""^INSERT INTO attachment VALUES\('\d+', '\d+', '\d+', '(.+)""") trim_r = re.compile(b"""(.+)', '\d+', '\d+'\);$""") extractor = re.compile(b"""^(.*(?:\.jpe?g|\.gif|\.bmp))', '(.+)$""") with open('attachments.sql', 'rb') as fh: for line in fh: data = trim_l.findall(line)[0] data = trim_r.findall(data)[0] data = extractor.findall(data) if data: name, data = data[0] try: filename = 'files/%s' % str(name, 'UTF-8') ah = open(filename, 'wb') ah.write(data) except UnicodeDecodeError: continue finally: ah.close() fh.close() update The JPEG wiki page says FF bytes are section markers, with the next byte indicating the section type. I see some that are not listed in the wiki page (specifically, I see a lot of 5C bytes, so FF5C). But the list is of "common markers" so I'm trying to find a more complete list. Any guidance here would also be appreciated.

    Read the article

  • How can I 'transpose' my data using SQL and remove duplicates at the same time?

    - by Remnant
    I have the following data structure in my database: LastName FirstName CourseName John Day Pricing John Day Marketing John Day Finance Lisa Smith Marketing Lisa Smith Finance etc... The data shows employess within a business and which courses they have shown a preference to attend. The number of courses per employee will vary (i.e. as above, John has 3 courses and Lisa 2). I need to take this data from the database and pass it to a webpage view (asp.net mvc). I would like the data that comes out of my database to match the view as much as possible and want to transform the data using SQl so that it looks like the following: LastName FirstName Course1 Course2 Course3 John Day Pricing Marketing Finance Lisa Smith Marketing Finance Any thoughts on how this may be achieved? Note: one of the reasons I am trying this approach is that the original data structure does not easily lend itself to be iterated over using the typical mvc syntax: <% foreach (var item in Model.courseData) { %> Because of the duplication of names in the orignal data I would end up with lots of conditionals in my View which I would like to avoid. I have tried transforming the data using c# in my ViewModel but have found it tough going and feel that I could lighten the workload by leveraging SQL before I return the data. Thanks.

    Read the article

  • C#/.Net Error: MySql.Data Object reference not set to an instance of an object.

    - by Simon
    Hello, I get this exception on my Windows 7 64bit in application running in VS 2008 express. I am using Connector/Net 6.2.2.0: Message: Object reference not set to an instance of an object. Source: MySql.Data in MySql.Data.MySqlClient.NativeDriver.GetResult(Int32& affectedRow, Int32& insertedId) Stack trace: in MySql.Data.MySqlClient.Driver.GetResult(Int32 statementId, Int32& affectedRows, Int32& insertedId) in MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId) in MySql.Data.MySqlClient.MySqlDataReader.NextResult() in MySql.Data.MySqlClient.MySqlDataReader.Close() in MySql.Data.MySqlClient.MySqlConnection.Close() in MySql.Data.MySqlClient.MySqlConnection.Dispose(Boolean disposing) in System.ComponentModel.Component.Finalize() No inner exception. This exception is unhalted and the debugger dont point on any code line. It just say "Object reference not set to an instance of an object. MySql.Data" This error is really hard to repeat. On my Windows XP 32bit is all ok. Could it be error in 64bit Windows 7? Thank you very much for your answers. Regards, simon

    Read the article

  • Access Expression problem: it's too complex, so how do I turn it in to a function?

    - by Mike
    Access 2007 is telling me that my new expression is to complex. It used to work when we had 10 service levels, but now we have 19! Great! I've asked this question in SuperUser and someone suggested I try it over here. Suggestions are I turn it in to a function - but I'm not sure where to begin and what the function would look like. My expression is checking the COST of our services in the [PriceCharged] field and then assigning the appropriate HOURS [Servicelevel] when I perform a calculation to work out how much REVENUE each colleague has made when working for a client. The [EstimatedTime] field stores the actual hours each colleague has worked. [EstimatedTime]/[ServiceLevel]*[PriceCharged] Below is the breakdown of my COST to HOURS expression. I've put them on different lines to make it easier to read - please do not be put off by the length of this post, it's all the same info in the end. Many thanks,Mike ServiceLevel: IIf([pricecharged]=100(COST),6(HOURS), IIf([pricecharged]=200 Or [pricecharged]=210,12.5, IIf([pricecharged]=300,19, IIf([pricecharged]=400 Or [pricecharged]=410,25, IIf([pricecharged]=500,31, IIf([pricecharged]=600,37.5, IIf([pricecharged]=700,43, IIf([pricecharged]=800 Or [pricecharged]=810,50, IIf([pricecharged]=900,56, IIf([pricecharged]=1000,62.5, IIf([pricecharged]=1100,69, IIf([pricecharged]=1200 Or [pricecharged]=1210,75, IIf([pricecharged]=1300 Or [pricecharged]=1310,100, IIf([pricecharged]=1400,125, IIf([pricecharged]=1500,150, IIf([pricecharged]=1600,175, IIf([pricecharged]=1700,200, IIf([pricecharged]=1800,225, IIf([pricecharged]=1900,250,0)))))))))))))))))))

    Read the article

  • PHP DomDocument class unable access domnode

    - by turbod
    Hi. I dont parse this url: http://foldmunka.net $ch = curl_init("http://foldmunka.net"); //curl_setopt($ch, CURLOPT_NOBODY, true); curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); //curl_setopt($ch, CURLOPT_HEADER, true); curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true); //not necessary unless the file redirects (like the PHP example we're using here) $data = curl_exec($ch); $info = curl_getinfo($ch); curl_close($ch); clearstatcache(); if ($data === false) { echo 'cURL failed'; exit; } $dom = new DOMDocument(); $data = mb_convert_encoding($data, 'HTML-ENTITIES', "utf-8"); $data = preg_replace('/<\!\-\-\[if(.*)\]>/', '', $data); $data = str_replace('<![endif]-->', '', $data); $data = str_replace('<!--', '', $data); $data = str_replace('-->', '', $data); $data = preg_replace('@<script[^>]*?>.*?</script>@si', '', $data); $data = preg_replace('@<style[^>]*?>.*?</style>@si', '', $data); $data = mb_convert_encoding($data, 'HTML-ENTITIES', "utf-8"); @$dom->loadHTML($data); $els = $dom->getElementsByTagName('*'); foreach($els as $el){ print $el->nodeName." | ".$el->getAttribute('content')."<hr />"; if($el->getAttribute('title'))$el->nodeValue = $el->getAttribute('title')." ".$el->nodeValue; if($el->getAttribute('alt'))$el->nodeValue = $el->getAttribute('alt')." ".$el->nodeValue; print $el->nodeName." | ".$el->nodeValue."<hr />"; } I need the alt, title attributes and the simple text, but this page i cannot access the nodes within the body tag.

    Read the article

  • How to send complex types from PHP SoapClient to ASP.NET SOAP server?

    - by xaguilars
    Hello I'm having problems sending arrays, structs and arrays of structs from PHP to an ASP.NET SOAP server... Anyone have a sollution for this? I've googled for days and any sollution worked for me. Perphaps I'm forgetting something... There are examples of my code: $client = new SoapClient($options); $pCriteria = new stdClass(); $pCriteria->type=1; $pCriteria->capacity=4; //Test 1 (fail): $resp = $client->GetRooms(array("pCriteria"=>$pCriteria)); //Test 2 (fail): $resp = $client->GetRooms(array("pCriteria"=>new SoapVar($pCriteria, SOAP_ENC_OBJECT, "TCriteria", "http://www.w3.org/2001/XMLSchema"))); print_r($resp); I don't know how to code functions that require an array of TCriteria (TCriteria[], TCriteria_Array type) either... i've tried sending the raw array, a SoapVar with SOAP_ENC_ARRAY encoding and TCriteria_Array type, ... but it does not work (the SOAP server becomes unavaiable and needs to be restarted). I've tried creating classes for the complex types too, instead of stdClass, but not working. I don't know where's the problem. The server admins cannot help me and I haven't found any sollution over internet. I'm a bit desperate hehe. Can you help me please? Can you provide samples of code with the three cases (array of simple data, array of struct and struct) ? Thanks!

    Read the article

  • MySQL Gurus: How to pull a complex grid of data from MySQL database with one query?

    - by iopener
    Hopefully this is less complex than I think. I have one table of companies, and another table of jobs, and a third table with that contains a single entry for each employee in each job from each company. NOTE: Some companies won't have employees in some jobs, and some companies will have more than one employee in some jobs. The company table has a companyid and companyname field, the job table has a jobid and jobtitle field, and the employee table has employeeid, companyid, jobid and employeename fields. I want to build a table like this: +-----------+-----------+-----------+ | Company A | Company B | Company C | ------+-----------+-----------+-----------+ Job A | Emp 1 | Emp 2 | | ------+-----------+-----------+-----------+ Job B | Emp 3 | | Emp 4 | | | | Emp 5 | ------+-----------+-----------+-----------+ Job C | | Emp 6 | | | | Emp 7 | | | | Emp 8 | | ------+-----------+-----------+-----------+ I had previously been looping through a result set of jobs, and for each job, looping through a result set of each company, and for each company, looping through each employee and printing it in a table (gross, but performance was not supposed to be a consideration). The app has grown in popularity, and now we have 100 companies and hundreds of jobs, and the server is crapping out (all the id fields are indexed). Any suggestions on how to write a single query to get this data? I don't need the company names or job titles (obviously), but I do need some way to identify where each row from the result should be printed. I'm imagining a result set that just contained a long list of joined employees, and I could write a loop to use the companyid and employeeid values to tell me when to create a new cell or table row. This works as long as there aren't ZERO employees; I would need a NULL employee name for that I think? Am I completely on the wrong track? Thanks in advance for any ideas!

    Read the article

  • How do I construct a more complex single LINQ to XML query?

    - by Cyberherbalist
    I'm a LINQ newbie, so the following might turn out to be very simple and obvious once it's answered, but I have to admit that the question is kicking my arse. Given this XML: <measuresystems> <measuresystem name="SI" attitude="proud"> <dimension name="mass" dim="M" degree="1"> <unit name="kilogram" symbol="kg"> <factor name="hundredweight" foreignsystem="US" value="45.359237" /> <factor name="hundredweight" foreignsystem="Imperial" value="50.80234544" /> </unit> </dimension> </measuresystem> </measuresystems> I can query for the value of the conversion factor between kilogram and US hundredweight using the following LINQ to XML, but surely there is a way to condense the four successive queries into a single complex query? XElement mss = XElement.Load(fileName); IEnumerable<XElement> ms = from el in mss.Elements("measuresystem") where (string)el.Attribute("name") == "SI" select el; IEnumerable<XElement> dim = from e2 in ms.Elements("dimension") where (string)e2.Attribute("name") == "mass" select e2; IEnumerable<XElement> unit = from e3 in dim.Elements("unit") where (string)e3.Attribute("name") == "kilogram" select e3; IEnumerable<XElement> factor = from e4 in unit.Elements("factor") where (string)e4.Attribute("name") == "pound" && (string)e4.Attribute("foreignsystem") == "US" select e4; foreach (XElement ex in factor) { Console.WriteLine ((string)ex.Attribute("value")); }

    Read the article

  • How to send an array of complex type in PHP using Soap_Client?

    - by xaguilars
    Hello I want to know how to send this array of complex data to a SOAP server (that uses .NET / IIS). <xs:complexType name="SampleStruct"> <xs:sequence> <xs:element name="title" type="xs:string"/> <xs:element name="description" type="xs:string"/> </xs:sequence> </xs:complexType> <xs:complexType name="SampleStruct_Array"> <xs:complexContent> <xs:restriction base="soapenc:Array"> <xs:sequence/> <xs:attribute ref="soapenc:arrayType" n1:arrayType="ns1:SampleStruct[]"/> </xs:restriction> </xs:complexContent> </xs:complexType> Would this code be ok? : $data1 = new SampleStruct(); $data1->title="Hello world"; $data1->description="This is a sample description."; $data2 = new SampleStruct(); $data2->title="Hello world 2"; $data2->description="This is a sample description 2."; $client->__soapCall("sampleFunction", array( new SoapParam(new SoapVar(array($data1, $data2) , SOAP_ENC_ARRAY, "SampleStruct_Array", "http://www.w3.org/2001/XMLSchema"), "theSampleFunctionParamName") )); Am I doing it ok? I'm not very familiar with Web services... Thank you

    Read the article

  • What's the most efficient way to load data from a file to a collection on-demand?

    - by Dan
    I'm working on a java project that will allows users to parse multiple files with potentially thousands of lines. The information parsed will be stored in different objects, which then will be added to a collection. Since the GUI won't require to load ALL these objects at once and keep them in memory, I'm looking for an efficient way to load/unload data from files, so that data is only loaded into the collection when a user requests it. I'm just evaluation options right now. I've also thought of the case where, after loading a subset of the data into the collection, and presenting it on the GUI, the best way to reload the previously observed data. Re-run the parser/Populate collection/Populate GUI? or probably find a way to keep the collection into memory, or serialize/deserialize the collection itself? I know that loading/unloading subsets of data can get tricky if some sort of data filtering is performed. Let's say that I filter on ID, so my new subset will contain data from two previous analyzed subsets. This would be no problem is I keep a master copy of the whole data in memory. I've read that google-collections are good and efficient when handling big amounts of data, and offer methods that simplify lots of things so this might offer an alternative to allow me to keep the collection in memory. This is just general talking. The question on what collection to use is a separate and complex thing. Do you know what's the general recommendation on this type of task? I'd like to hear what you've done with similar scenarios. I can provide more specifics if needed.

    Read the article

  • How to create a generic method in C# that's all applicable to many types - ints, strings, doubles et

    - by satyajit
    Let's I have a method to remove duplicates in an integer Array public int[] RemoveDuplicates(int[] elems) { HashSet<int> uniques = new HashSet<int>(); foreach (int item in elems) uniques.Add(item); elems = new int[uniques.Count]; int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } How can I make this generic such that now it accepts a string array and remove duplicates in it? How about a double array? I know I am probably mixing things here in between primitive and value types. For your reference the following code won't compile public List<T> RemoveDuplicates(List<T> elems) { HashSet<T> uniques = new HashSet<T>(); foreach (var item in elems) uniques.Add(item); elems = new List<T>(); int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } The reason is that all generic types should be closed at run time. Thanks for you comments

    Read the article

  • How to have variables with dynamic data types in Java?

    - by Nazgulled
    Hi, I need to have a UserProfile class that it's just that, a user profile. This user profile has some vital user data of course, but it also needs to have lists of messages sent from the user friends. I need to save these messages in LinkedList, ArrayList, HashMap and TreeMap. But only one at a time and not duplicate the message for each data structure. Basically, something like a dynamic variable type where I could pick the data type for the messages. Is this, somehow, possible in Java? Or my best approach is something like this? I mean, have 2 different classes (for the user profile), one where I host the messages as Map<K,V> (and then I use HashMap and TreeMap where appropriately) and another class where I host them as List<E> (and then I use LinkedList and ArrayList where appropriately). And probably use a super class for the UserProfile so I don't have to duplicate variables and methods for fields like data, age, address, etc... Any thoughts?

    Read the article

  • When to use basic types (Integer, String), and when to write a new class?

    - by belgarat
    Stackoverflow users: A lot of things can be represented in programs by using the basic types, or we can create a new class for it. Example: A social security number can be a number, string or its own object. (Other common examples: Phone numbers, names, zip codes, user id, order id and other id's.) My question is: When should the basic types be used, and when should we write ourselves a new class? I see that when you need to add behavior, you'll want to create a class (example, social security number parsing, validation, formatting, etc). But is this the only criteria? I have come across cases where many of these things are represented as java Integers and/or Strings. We loose the benefit of type-checking, and I have often seen bugs caused by parameters being mixed in calls to function(Intever, Integer, Integer, Integer). On the other hand, some programmers are opposed to over-designing by creating classes for "eveything". Obviously, the answer is "it depends". But, what do you think, and what do you normally do?

    Read the article

  • SQL SERVER – Beginning of SQL Server Architecture – Terminology – Guest Post

    - by pinaldave
    SQL Server Architecture is a very deep subject. Covering it in a single post is an almost impossible task. However, this subject is very popular topic among beginners and advanced users.  I have requested my friend Anil Kumar who is expert in SQL Domain to help me write  a simple post about Beginning SQL Server Architecture. As stated earlier this subject is very deep subject and in this first article series he has covered basic terminologies. In future article he will explore the subject further down. Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. In this Article we will discuss about MS SQL Server architecture. The major components of SQL Server are: Relational Engine Storage Engine SQL OS Now we will discuss and understand each one of them. 1) Relational Engine: Also called as the query processor, Relational Engine includes the components of SQL Server that determine what your query exactly needs to do and the best way to do it. It manages the execution of queries as it requests data from the storage engine and processes the results returned. Different Tasks of Relational Engine: Query Processing Memory Management Thread and Task Management Buffer Management Distributed Query Processing 2) Storage Engine: Storage Engine is responsible for storage and retrieval of the data on to the storage system (Disk, SAN etc.). to understand more, let’s focus on the following diagram. When we talk about any database in SQL server, there are 2 types of files that are created at the disk level – Data file and Log file. Data file physically stores the data in data pages. Log files that are also known as write ahead logs, are used for storing transactions performed on the database. Let’s understand data file and log file in more details: Data File: Data File stores data in the form of Data Page (8KB) and these data pages are logically organized in extents. Extents: Extents are logical units in the database. They are a combination of 8 data pages i.e. 64 KB forms an extent. Extents can be of two types, Mixed and Uniform. Mixed extents hold different types of pages like index, System, Object data etc. On the other hand, Uniform extents are dedicated to only one type. Pages: As we should know what type of data pages can be stored in SQL Server, below mentioned are some of them: Data Page: It holds the data entered by the user but not the data which is of type text, ntext, nvarchar(max), varchar(max), varbinary(max), image and xml data. Index: It stores the index entries. Text/Image: It stores LOB ( Large Object data) like text, ntext, varchar(max), nvarchar(max),  varbinary(max), image and xml data. GAM & SGAM (Global Allocation Map & Shared Global Allocation Map): They are used for saving information related to the allocation of extents. PFS (Page Free Space): Information related to page allocation and unused space available on pages. IAM (Index Allocation Map): Information pertaining to extents that are used by a table or index per allocation unit. BCM (Bulk Changed Map): Keeps information about the extents changed in a Bulk Operation. DCM (Differential Change Map): This is the information of extents that have modified since the last BACKUP DATABASE statement as per allocation unit. Log File: It also known as write ahead log. It stores modification to the database (DML and DDL). Sufficient information is logged to be able to: Roll back transactions if requested Recover the database in case of failure Write Ahead Logging is used to create log entries Transaction logs are written in chronological order in a circular way Truncation policy for logs is based on the recovery model SQL OS: This lies between the host machine (Windows OS) and SQL Server. All the activities performed on database engine are taken care of by SQL OS. It is a highly configurable operating system with powerful API (application programming interface), enabling automatic locality and advanced parallelism. SQL OS provides various operating system services, such as memory management deals with buffer pool, log buffer and deadlock detection using the blocking and locking structure. Other services include exception handling, hosting for external components like Common Language Runtime, CLR etc. I guess this brief article gives you an idea about the various terminologies used related to SQL Server Architecture. In future articles we will explore them further. Guest Author  The author of the article is Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

    Read the article

  • Logical Domain Modeling Made Simple

    - by Knut Vatsendvik
    How can logical domain modeling be made simple and collaborative? Many non-technical end-users, managers and business domain experts find it difficult to understand the visual models offered by many UML tools. This creates trouble in capturing and verifying the information that goes into a logical domain model. The tools are also too advanced and complex for a non-technical user to learn and use. We have therefore, in our current project, ended up with using Confluence as tool for designing the logical domain model with the help of a few very useful plugins. Big thanks to Ole Nymoen and Per Spilling for their expertise in this field that made this posting possible. Confluence Plugins Here is a list of Confluence plugins used in this solution. Install these before trying out the macros used below. Plugin Description Copy Space Allows a space administrator to copy a space, including the pages within the space Metadata Supports adding metadata to Wiki pages Label Manages labeling of pages Linking Contains macros for linking to templates, the dashboard and other Table Enhances the table capability in Confluence Creating a Confluence Space First we need to create a new confluence space for the domain model. Click the link Create a Space located below the list of spaces on the Dashboard. Please contact your Confluence administrator is you do not have permissions to do this.   For illustrative purpose all attributes and entities in this posting are based on my imaginary project manager domain model. When a logical domain model is good enough for being implemented, do a copy of the Confluence Space (see Copy Space plugin). In this way you create a stable version of the logical domain model while further design can continue with the new copied space. Typical will the implementation phase result in a database design and/or a XSD schema design. Add Space Templates Go to the Home page of your Confluence Space. Navigate to the Browse drop-down menu and click on Advanced. Then click the Templates option in the left navigation panel. Click Add New Space Template to add the following three templates. Name: attribute {metadata-list} || Name | | || Type | | || Format | | || Description | | {metadata-list} {add-label:attribute} Name: primary-type {metadata-list} || Name | || || Type | || || Format | || || Description | || {metadata-list} {add-label:primary-type} Name: complex-type {metadata-list} || Name | || || Description |  || {metadata-list} h3. Attributes || Name || Type || Format || Description || | [name] | {metadata-from:name|Type} | {metadata-from:name|Format} | {metadata-from:name|Description} | {add-label:complex-type,entity} The metadata-list macro (see Metadata plugin) will save a list of metadata values to the page. The add-label macro (see Label plugin) will automatically label the page. Primary Types Page Our first page to add will act as container for our primary types. Switch to Wiki markup when adding the following content to the page. | (+) {add-page:template=primary-type|parent=@self}Add new primary type{add-page} | {metadata-report:Name,Type,Format,Description|sort=Name|root=@self|pages=@descendents} Once the page is created, click the Add new primary type (create-page macro) to start creating a new pages. Here is an example of input to the LocalDate page. Embrace the LocalDate with square brackets [] to make the page linkable. Again switch to Wiki markup before editing. {metadata-list} || Name | [LocalDate] || || Type | Date || || Format | YYYY-MM-DD || || Description | Date in local time zone. YYYY = year, MM = month and DD = day || {metadata-list} {add-label:primary-type} The metadata-report macro will show a tabular report of all child pages.   Attributes Page The next page will act as container for all of our attributes. | (+) {add-page:template=attribute|parent=@self|title=attribute}Add new attribute{add-page} | {metadata-report:Name,Type,Format,Description|sort=Name|pages=@descendants} Here is an example of input to the startDate page. {metadata-list} || Name | [startDate] || || Type | [LocalDate] || || Format | {metadata-from:LocalDate|Format} || || Description | The projects start date || {metadata-list} {add-label:attribute} Using the metadata-from macro we fetch the text from the previously created LocalDate page. Complex Types Page The last page in this example shows how attributes can be combined together to form more complex types.   h3. Intro Overview of complex types in the domain model. | (+) {add-page:template=complex-type|parent=@self}Add a new complex type{add-page}\\ | {metadata-report:Name,Description|sort=Name|root=@self|pages=@descendents} Here is an example of input to the ProjectType page. {metadata-list} || Name | [ProjectType] || || Description | Represents a project || {metadata-list} h3. Attributes || Name || Type || Format || Description || | [projectId] | {metadata-from:projectId|Type} | {metadata-from:projectId|Format} | {metadata-from:projectId|Description} | | [name] | {metadata-from:name|Type} | {metadata-from:name|Format} | {metadata-from:name|Description} | | [description] | {metadata-from:description|Type} | {metadata-from:description|Format} | {metadata-from:description|Description} | | [startDate] | {metadata-from:startDate|Type} | {metadata-from:startDate|Format} | {metadata-from:startDate|Description} | {add-label:complex-type,entity} Gives us this Conclusion Using a web-based corporate Wiki like Confluence to create a logical domain model increases the collaboration between people with different roles in the enterprise. It’s my believe that this helps the domain model to be more accurate, and better documented. In our real project we have more pages than illustrated here to complete the documentation. We do also still use UML tools to create different types of diagrams that Confluence do not support. As a last tip, an ImageMap plugin can make those diagrams clickable when used in pages. Enjoy!

    Read the article

< Previous Page | 459 460 461 462 463 464 465 466 467 468 469 470  | Next Page >