Search Results

Search found 1851 results on 75 pages for 'constraint layouts'.

Page 21/75 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • SQL Server Constraints Across Tables

    - by chama
    I have a SQL Server database with an Apartment table (which has columns FloorNum and BuildingID) and an ApartmentBuilding table (with column NumFloors). Is there any way to set up a constraint (using the SQL Server UI) to check that Apartment.FloorNum is greater than ApartmentBuilding.NumFloors? I tried this: FloorNum > ApartmentBuilding.NumFloors but now I realize that I somehow have to join the columns on the BuildingID, but I have no idea how to do that within a constraint. Thanks for your help!

    Read the article

  • Add not null DateTime column to SQLite without default value?

    - by acidzombie24
    It looks like i cant add a not null constraint or remove a default constraint. I would like to add a datetime column to a table and have all the values set to anything (perhaps 1970 or year 2000) but it seems like i cant use not null without a default and i cant remove a default once added in. So how can i add this column? (once again just a plain datetime not null)

    Read the article

  • Necessary rights to be able to add a column with ALTER TABLE ADD column_name

    - by Sorin Comanescu
    Hi, Could somebody point out the necessary rights to do something like ALTER TABLE myTable ADD myColumn int NOT NULL CONSTRAINT [Constraint_name] DEFAULT ((0)) ? I assumed grant alter on myTable to [user] was enough but I'm getting the error message The UPDATE permission was denied on the object 'myTable', database 'x', schema 'dbo'. Could UPDATE rights be needed because of the DEFAULT constraint? Thanks.

    Read the article

  • Is this postgres function cost efficient or still have to clean

    - by kiranking
    There are two tables in postgres db. english_all and english_glob First table contains words like international,confidential,booting,cooler ...etc I have written the function to get the words from english_all then perform for loop for each word to get word list which are not inserted in anglish_glob table. Word list is like I In Int Inte Inter .. b bo boo boot .. c co coo cool etc.. for some reason zwnj(zero-width non-joiner) is added during insertion to english_all table. But in function I am removing that character with regexp_replace. Postgres function for_loop_test is taking two parameter min and max based on that I am selecting words from english_all table. function code is like DECLARE inMinLength ALIAS FOR $1; inMaxLength ALIAS FOR $2; mviews RECORD; outenglishListRow english_word_list;--custom data type eng_id,english_text BEGIN FOR mviews IN SELECT id,english_all_text FROM english_all where wlength between inMinLength and inMaxLength ORDER BY english_all_text limit 30 LOOP FOR i IN 1..char_length(regexp_replace(mviews.english_all_text,'(?)$','')) LOOP FOR outenglishListRow IN SELECT distinct on (regexp_replace((substring(mviews.english_all_text from 1 for i)),'(?)$','')) mviews.id, regexp_replace((substring(mviews.english_all_text from 1 for i)),'(?)$','') where regexp_replace((substring(mviews.english_all_text from 1 for i)),'(?)$','') not in(select english_glob.english_text from english_glob where i=english_glob.wlength) order by regexp_replace((substring(mviews.english_all_text from 1 for i)),'(?)$','') LOOP RETURN NEXT outenglishListRow; END LOOP; END LOOP; END LOOP; END; Once I get the word list I will insert that into another table english_glob. My question is is there any thing I can add to or remove from function to make it more efficient. edit Let assume english_all table have words like footer,settle,question,overflow,database,kingdom If inMinLength = 5 and inmaxLength=7 then in the outer loop footer,settle,kingdom will be selected. For above 3 words inner two loop will apply to get words like f,fo,foo,foot,foote,footer,s,se,set,sett,settl .... etc. In the final process words which are bold will be entered into english_glob with another parameter like 1 to denote it is a proper word and stored in the another filed of english_glob table. Remaining word will be stored with another parameter 0 because in the next call words which are saved in database should not be fetched again. edit2: This is a complete code CREATE TABLE english_all ( id serial NOT NULL, english_all_text text NOT NULL, wlength integer NOT NULL, CONSTRAINT english_all PRIMARY KEY (id), CONSTRAINT english_all_kan_text_uq_id UNIQUE (english_all_text) ) CREATE TABLE english_glob ( id serial NOT NULL, english_text text NOT NULL, is_prop integer default 1, CONSTRAINT english_glob PRIMARY KEY (id), CONSTRAINT english_glob_kan_text_uq_id UNIQUE (english_text) ) insert into english_all(english_text) values ('ant'),('forget'),('forgive'); on function call with parameter 3 and 6 fallowing rows should fetched a an ant f fo for forg forge forget next is insert to another table based on above row insert into english_glob(english_text,is_prop) values ('a',1),('an',1), ('ant',1),('f',0), ('fo',0),('for',1), ('forg',0),('forge',1), ('forget',1), on function call next time with parameter 3 and 7 fallowing rows should fetched.(because f,fo,for,forg are all entered in english_glob table) forgi forgiv forgive

    Read the article

  • Generic Type Parameter constraints in C# .NET

    - by activwerx
    Consider the following Generic class: public class Custom<T> where T : string { } This produces the following error: 'string' is not a valid constraint. A type used as a constraint must be an interface, a non-sealed class or a type parameter. Is there another way to constrain which types my generic class can use? Also, can I constrain to multiple types? E.G. T can only be string, int or byte

    Read the article

  • Spring's JdbcDaoSupport (using MySQL Connector/J) fails after executing sql that adds FK

    - by John
    I am using Spring's JdbcDaoSupport class with a DriverManagerDataSource using the MySQL Connector/J 5.0 driver (driverClassName=com.mysql.jdbc.driver). allowMultiQueries is set to true in the url. My application is an in-house tool we recently developed that executes sql scripts in a directory one-by-one (allows us to re-create our schema and reference table data for a given date, etc, but I digress). The sql scripts sometime contain multiple statements (hence allowMultiQueries), so one script can create a table, add indexes for that table, etc. The problem happens when including a statement to add a foreign key constraint in one of these files. If I have a file that looks like... --(column/constraint names are examples) CREATE TABLE myTable ( fk1 BIGINT(19) NOT NULL, fk2 BIGINT(19) NOT NULL, PRIMARY KEY (fk1, fk2) ); ALTER TABLE myTable ADD CONSTRAINT myTable_fk1 FOREIGN KEY (fk1) REFERENCES myOtherTable (id) ; ALTER TABLE myTable ADD CONSTRAINT myTable_fk2 FOREIGN KEY (fk2) REFERENCES myOtherOtherTable (id) ; then JdbcTemplate.execute throws an UncategorizedSqlException with the following error message and stack trace: Exception in thread "main" org.springframework.jdbc.UncategorizedSQLException: StatementCallback; uncategorized SQLException for SQL [ THE SQL YOU SEE ABOVE LISTED HERE ]; SQL state [HY000]; error code [1005]; Can't create table 'myDatabase.myTable' (errno: 150); nested exception is java.sql.SQLException: Can't create table 'myDatabase.myTable' (errno: 150) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:83) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80) and the table and foreign keys are not inserted. Also, especially weird: if I take the foreign key statements out of the script I showed above and then place them in their own script that executes after (so I now have 1 script with just the create table statement, and 1 script with the add foreign key statements that executes after that) then what happens is: tool executes create table script, works fine, table is created tool executes add fk script, throws the same exception as seen above (except errno=121 this time), but the FKs actually get added (!!!) In other words, when the create table/FK statements are in the same script then the exception is thrown and nothing is created, but when they are different scripts a nearly identical exception is thrown but both things get created. Any help on this would be greatly appreciated. Please let me know if you'd like me to clarify anything more.

    Read the article

  • Any tools or techniques for validating constraints programmatically between databases?

    - by Brandon
    If you had two databases, that had two tables between them that would normally implement a one to one (or many to many) constraint but cannot since they are separate databases, how would you validate this relationship in an application or test? Is there a simple way to do this? For example, a tool or technique that can, given a constraint type, tables and fields, does the validation. I imagine that this isn't the first time this come up so I'm hoping people can share their solution. Thanks.

    Read the article

  • mysql circular dependency in foreign key constraints

    - by Flavius
    Given the schema: What I need is having every user_identities.belongs_to reference an users.id. At the same time, every users has a primary_identity as shown in the picture. However when I try to add this reference with ON DELETE NO ACTION ON UPDATE NO ACTION, MySQL says #1452 - Cannot add or update a child row: a foreign key constraint fails (yap.#sql-a3b_1bf, CONSTRAINT #sql-a3b_1bf_ibfk_1 FOREIGN KEY (belongs_to) REFERENCES users (id) ON DELETE NO ACTION ON UPDATE NO ACTION) I suspect this is due to the circular dependency, but how could I solve it (and maintain referential integrity)?

    Read the article

  • How to Auto-Increment Non-Primary Key? - SQL Server

    - by user311509
    CREATE TABLE SupplierQuote ( supplierQuoteID int identity (3504,2) CONSTRAINT supquoteid_pk PRIMARY KEY, PONumber int identity (9553,20) NOT NULL . . . CONSTRAINT ponumber_uq UNIQUE(PONumber) ); The above ddl produces an error: Msg 2744, Level 16, State 2, Line 1 Multiple identity columns specified for table 'SupplierQuote'. Only one identity column per table is allowed. How can i solve it? I want PONumber to be auto-incremented.

    Read the article

  • Javascript Graph Layout Engine

    - by GJK
    I'm looking for a Javascript library/engine that can do graph layouts. (And when I say layouts, I mean logically position vertices nicely.) The graphs I'm working with are all m-ary trees. M is usually no more than 5 or 6, but it can be greater in some cases. I do have something that I use now, Graphviz's node program, and it works perfectly. The problem is, when running a web app, I have to send a request to the server every time I want a layout. Preferably, I would like something written in Javascript that can be quickly run on the client side. All it needs to do is provide layout information (relative positioning and whatnot). I don't need it to draw to a canvas or use SVG or anything, all I'm interested in is the layout. Library use like jQuery or RaphaelJS is fine by me. I'll work with it. I'm just looking for something to speed things along a little. Also, I'd consider writing my own if I could find a nice description of an algorithm to do the layouts. But I really don't want to spend too much time. I have something that works now, so getting it on the client side is just a bonus, not a necessity.

    Read the article

  • Method-Object pairs in Java

    - by John Manak
    I'd like to create a list of method-object pairs. Each method is a function returning a boolean. Then: foreach(pair) { if method evaluates to true { do something with the object } } One way of modelling this that I can think of is to have a class Constraint with a method isValid() and for each constraint produce an anonymous class (overriding the isValid() method). I feel like there could be a nicer way. Can you think of any?

    Read the article

  • SQL SERVER Spatial Data

    - by Sam
    Hi All, I am struggeling finding an effectient way to find a distance between a Point that interetcts a polygon and the border of that polygon. I was able to use the STDistance comparing the point to every point that made up the polygon but that is taking a lot of time. Using SPatial indexed wasnt much helpful because the STDistance is not part of any constraint and even when I did put the constraint, the index didnt help much. I appreciate any feedback. Thanks.

    Read the article

  • mysql error dont understand what it is saying

    - by sea_1987
    Cannot add or update a child row: a foreign key constraint fails (`mydb`.`job_listing_has_employer_details`, CONSTRAINT `job_listing_has_employer_details_ibfk_2` FOREIGN KEY (`employer_details_id`) REFERENCES `employer_details` (`id`)) INSERT INTO `job_listing_has_employer_details` (`job_listing_id`, `employer_details_id`) VALUES (6, '5') What does this mean? The two ID's I am inserting into the table exsist.

    Read the article

  • What does ON [PRIMARY] mean?

    - by Icono123
    I'm creating an SQL setup script and I'm using someone else's script as an example. Here's an example of the script: SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[be_Categories]( [CategoryID] [uniqueidentifier] ROWGUIDCOL NOT NULL CONSTRAINT [DF_be_Categories_CategoryID] DEFAULT (newid()), [CategoryName] [nvarchar](50) NULL, [Description] [nvarchar](200) NULL, [ParentID] [uniqueidentifier] NULL, CONSTRAINT [PK_be_Categories] PRIMARY KEY CLUSTERED ( [CategoryID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO Does anyone know what the ON [PRIMARY] command does? Regards.

    Read the article

  • Software or Photoshop plugins for professional photo album design

    - by Iain Fraser
    I am a graphic designer (among other things) and I'm used to doing magazine advertisements, brochures, posters and that sort of thing. Recently I was approached by a photographer who wants a graphic designer to produce wedding albums for him. I have already done a couple for him but I'm finding it hard to work by just arranging my layouts in Photoshop alone. It's very time consuming, but quite repetitive - especially when you're dealing with common page layouts. I know a lot of photographers use album design software to speed up the process a bit. What's the industry standard in terms of album design software?

    Read the article

  • Passing multiple Vertex Attributes in GLSL 130

    - by Roy T.
    (note this question is closely related to this one however I didn't fully understand the accepted answer) To support videocards in laptops I have to rewrite my GLSL 330 shaders to GLSL 130. I'm trying to do this but somehow I don't get vertex attributes to work properly. My 330 shaders look like this: #version 330 layout(location = 0) in vec4 position; layout(location = 3) in vec4 color; smooth out vec4 theColor; void main() { gl_Position = position; theColor = color; } Now this explicit layout is not allowed in GLSL 130 so I referenced this page to see what the default layouts for some values would be. As you can see position should be the 0th vertex attribute and color should be the 3rd vertex attribute. Because this is a test case I had already configured my explicit layouts in the same way, which worked, so I now simply rewrote my shader to this and expected it to work: #version 130 smooth out vec4 theColor; void main() { gl_Position = gl_Vertex; theColor = gl_Color; } However this doesn't work, the value of gl_Color is always (1,1,1,1). So how should I pass multiple vertex attributes to my GLSL 130 shaders? For reference, this is how I set my vertex buffer object and attributes (I've just adapted this tutorial to JAVA+JOGL) gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, vertex_buffer_id); gl.glEnableVertexAttribArray(0); gl.glEnableVertexAttribArray(3); gl.glVertexAttribPointer(0, 4 , GL3.GL_FLOAT, false, 0, 0); gl.glVertexAttribPointer(3, 4, GL3.GL_FLOAT, false, 0, 4*4*4); gl.glDrawArrays(GL3.GL_TRIANGLE_STRIP, 0, 4); gl.glDisableVertexAttribArray(0); gl.glDisableVertexAttribArray(3); EDIT I solved the problem by querying for the layout locations of position an color using glGetAttribLocation however I still don't understand why the 'hardcoded' values like gl_Color didn't work, can't I upload data in there as normal? Shouldn't they be used?

    Read the article

  • Diagnosing xmodmap errors

    - by intuited
    I'm getting this error when trying to use xmodmap to get rid of caps lock: $ xmodmap -e 'clear Lock' X Error of failed request: BadValue (integer parameter out of range for operation) Major opcode of failed request: 118 (X_SetModifierMapping) Value in failed request: 0x17 Serial number of failed request: 8 Current serial number in output stream: 8 I'm running xfce on Maverick "10.10" Meercat. This problem did not occur before I added the Keyboard Layouts applet to a panel; before doing that, I was able to run my xmodmap script to swap Esc and CapsLock: !Remap Caps_Lock as Escape remove Lock = Caps_Lock keysym Caps_Lock = Escape It may be relevant that I chose alt-capslock as the keyboard switch combo in the Keyboard Layouts preferences. I've had a similar problem before, on a different machine, running openbox. On that machine, this problem started when I upgraded to Lucid, and has persisted in Maverick (release 10.10). I reported a bug in xorg. However, it remains unclear whether it's really a problem with xorg, or if I'm just doing something wrong with my configuration. Have other people experienced this problem? Can someone shed some light on what's going on here? It seems there are quite a few layers involved, and I don't understand any of them particularly well, so any information would be helpful. update I've discovered that the problem is specifically triggered by adding the Canada layout variant "Multilingual" (ca-multix). If I instead add the variant "Multilingual (first part)", the problem does not occur. I think this will probably end up being a usable workaround, but I don't yet know what the difference between these variants is. I've filed a freedesktop issue, and am commenting on a related ubuntu issue.

    Read the article

  • T-SQL Tuesday #31 - Logging Tricks with CONTEXT_INFO

    - by Most Valuable Yak (Rob Volk)
    This month's T-SQL Tuesday is being hosted by Aaron Nelson [b | t], fellow Atlantan (the city in Georgia, not the famous sunken city, or the resort in the Bahamas) and covers the topic of logging (the recording of information, not the harvesting of trees) and maintains the fine T-SQL Tuesday tradition begun by Adam Machanic [b | t] (the SQL Server guru, not the guy who fixes cars, check the spelling again, there will be a quiz later). This is a trick I learned from Fernando Guerrero [b | t] waaaaaay back during the PASS Summit 2004 in sunny, hurricane-infested Orlando, during his session on Secret SQL Server (not sure if that's the correct title, and I haven't used parentheses in this paragraph yet).  CONTEXT_INFO is a neat little feature that's existed since SQL Server 2000 and perhaps even earlier.  It lets you assign data to the current session/connection, and maintains that data until you disconnect or change it.  In addition to the CONTEXT_INFO() function, you can also query the context_info column in sys.dm_exec_sessions, or even sysprocesses if you're still running SQL Server 2000, if you need to see it for another session. While you're limited to 128 bytes, one big advantage that CONTEXT_INFO has is that it's independent of any transactions.  If you've ever logged to a table in a transaction and then lost messages when it rolled back, you can understand how aggravating it can be.  CONTEXT_INFO also survives across multiple SQL batches (GO separators) in the same connection, so for those of you who were going to suggest "just log to a table variable, they don't get rolled back":  HA-HA, I GOT YOU!  Since GO starts a new batch all variable declarations are lost. Here's a simple example I recently used at work.  I had to test database mirroring configurations for disaster recovery scenarios and measure the network throughput.  I also needed to log how long it took for the script to run and include the mirror settings for the database in question.  I decided to use AdventureWorks as my database model, and Adam Machanic's Big Adventure script to provide a fairly large workload that's repeatable and easily scalable.  My test would consist of several copies of AdventureWorks running the Big Adventure script while I mirrored the databases (or not). Since Adam's script contains several batches, I decided CONTEXT_INFO would have to be used.  As it turns out, I only needed to grab the start time at the beginning, I could get the rest of the data at the end of the process.   The code is pretty small: declare @time binary(128)=cast(getdate() as binary(8)) set context_info @time   ... rest of Big Adventure code ...   go use master; insert mirror_test(server,role,partner,db,state,safety,start,duration) select @@servername, mirroring_role_desc, mirroring_partner_instance, db_name(database_id), mirroring_state_desc, mirroring_safety_level_desc, cast(cast(context_info() as binary(8)) as datetime), datediff(s,cast(cast(context_info() as binary(8)) as datetime),getdate()) from sys.database_mirroring where db_name(database_id) like 'Adv%';   I declared @time as a binary(128) since CONTEXT_INFO is defined that way.  I couldn't convert GETDATE() to binary(128) as it would pad the first 120 bytes as 0x00.  To keep the CAST functions simple and avoid using SUBSTRING, I decided to CAST GETDATE() as binary(8) and let SQL Server do the implicit conversion.  It's not the safest way perhaps, but it works on my machine. :) As I mentioned earlier, you can query system views for sessions and get their CONTEXT_INFO.  With a little boilerplate code this can be used to monitor long-running procedures, in case you need to kill a process, or are just curious  how long certain parts take.  In this example, I added code to Adam's Big Adventure script to set CONTEXT_INFO messages at strategic places I want to monitor.  (His code is in UPPERCASE as it was in the original, mine is all lowercase): declare @msg binary(128) set @msg=cast('Altering bigProduct.ProductID' as binary(128)) set context_info @msg go ALTER TABLE bigProduct ALTER COLUMN ProductID INT NOT NULL GO set context_info 0x0 go declare @msg1 binary(128) set @msg1=cast('Adding pk_bigProduct Constraint' as binary(128)) set context_info @msg1 go ALTER TABLE bigProduct ADD CONSTRAINT pk_bigProduct PRIMARY KEY (ProductID) GO set context_info 0x0 go declare @msg2 binary(128) set @msg2=cast('Altering bigTransactionHistory.TransactionID' as binary(128)) set context_info @msg2 go ALTER TABLE bigTransactionHistory ALTER COLUMN TransactionID INT NOT NULL GO set context_info 0x0 go declare @msg3 binary(128) set @msg3=cast('Adding pk_bigTransactionHistory Constraint' as binary(128)) set context_info @msg3 go ALTER TABLE bigTransactionHistory ADD CONSTRAINT pk_bigTransactionHistory PRIMARY KEY NONCLUSTERED(TransactionID) GO set context_info 0x0 go declare @msg4 binary(128) set @msg4=cast('Creating IX_ProductId_TransactionDate Index' as binary(128)) set context_info @msg4 go CREATE NONCLUSTERED INDEX IX_ProductId_TransactionDate ON bigTransactionHistory(ProductId,TransactionDate) INCLUDE(Quantity,ActualCost) GO set context_info 0x0   This doesn't include the entire script, only those portions that altered a table or created an index.  One annoyance is that SET CONTEXT_INFO requires a literal or variable, you can't use an expression.  And since GO starts a new batch I need to declare a variable in each one.  And of course I have to use CAST because it won't implicitly convert varchar to binary.  And even though context_info is a nullable column, you can't SET CONTEXT_INFO NULL, so I have to use SET CONTEXT_INFO 0x0 to clear the message after the statement completes.  And if you're thinking of turning this into a UDF, you can't, although a stored procedure would work. So what does all this aggravation get you?  As the code runs, if I want to see which stage the session is at, I can run the following (assuming SPID 51 is the one I want): select CAST(context_info as varchar(128)) from sys.dm_exec_sessions where session_id=51   Since SQL Server 2005 introduced the new system and dynamic management views (DMVs) there's not as much need for tagging a session with these kinds of messages.  You can get the session start time and currently executing statement from them, and neatly presented if you use Adam's sp_whoisactive utility (and you absolutely should be using it).  Of course you can always use xp_cmdshell, a CLR function, or some other tricks to log information outside of a SQL transaction.  All the same, I've used this trick to monitor long-running reports at a previous job, and I still think CONTEXT_INFO is a great feature, especially if you're still using SQL Server 2000 or want to supplement your instrumentation.  If you'd like an exercise, consider adding the system time to the messages in the last example, and an automated job to query and parse it from the system tables.  That would let you track how long each statement ran without having to run Profiler. #TSQL2sDay

    Read the article

  • From .psd to working HTML and CSS - help me suck less

    - by kevinmajor1
    I am not much of a designer. My strength lies in coding. That said, I'm often forced into the role of "The Man," responsible for all aspects of site creation. So, that said I'm wondering if the pros can give me tips/solutions/links to tutorials to my main questions. Resolution. What should I aim for? What are the lower and upper edges I should be aware of? I know that systems like 960 Grid were popular recently. Is that the number I should still aim for? Slicing up a .psd - are there any tricks I should know? I've always found it difficult to get my slices pixel perfect. I'm also really slow at it. I must be looking at it wrong, or missing something fundamental. The same goes for text. Layouts are always filled with the classic "Lorem...", but I can never seem to get real content to fit quite as well on the screen. The advanced (to me, anyway) looking things, like a part of a logo/image overlaying what looks like a content area. How does one do that? How do layouts change/are informed by the decision to go fixed or liquid? Again, any tips/tricks/suggestions/tutorials you can share would be greatly appreciated.

    Read the article

  • SQL SERVER – Weekly Series – Memory Lane – #034

    - 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 UDF – User Defined Function to Strip HTML – Parse HTML – No Regular Expression The UDF used in the blog does fantastic task – it scans entire HTML text and removes all the HTML tags. It keeps only valid text data without HTML task. This is one of the quite commonly requested tasks many developers have to face everyday. De-fragmentation of Database at Operating System to Improve Performance Operating system skips MDF file while defragging the entire filesystem of the operating system. It is absolutely fine and there is no impact of the same on performance. Read the entire blog post for my conversation with our network engineers. Delay Function – WAITFOR clause – Delay Execution of Commands How do you delay execution of the commands in SQL Server – ofcourse by using WAITFOR keyword. In this blog post, I explain the same with the help of T-SQL script. Find Length of Text Field To measure the length of TEXT fields the function is DATALENGTH(textfield). Len will not work for text field. As of SQL Server 2005, developers should migrate all the text fields to VARCHAR(MAX) as that is the way forward. Retrieve Current Date Time in SQL Server CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} There are three ways to retrieve the current datetime in SQL SERVER. CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} Explanation and Comparison of NULLIF and ISNULL An interesting observation is NULLIF returns null if it comparison is successful, whereas ISNULL returns not null if its comparison is successful. In one way they are opposite to each other. Here is my question to you - How to create infinite loop using NULLIF and ISNULL? If this is even possible? 2008 Introduction to SERVERPROPERTY and example SERVERPROPERTY is a very interesting system function. It returns many of the system values. I use it very frequently to get different server values like Server Collation, Server Name etc. SQL Server Start Time We can use DMV to find out what is the start time of SQL Server in 2008 and later version. In this blog you can see how you can do the same. Find Current Identity of Table Many times we need to know what is the current identity of the column. I have found one of my developers using aggregated function MAX () to find the current identity. However, I prefer following DBCC command to figure out current identity. Create Check Constraint on Column Some time we just need to create a simple constraint over the table but I have noticed that developers do many different things to make table column follow rules than just creating constraint. I suggest constraint is a very useful concept and every SQL Developer should pay good attention to this subject. 2009 List Schema Name and Table Name for Database This is one of the blog post where I straight forward display script. One of the kind of blog posts, which I still love to read and write. Clustered Index on Separate Drive From Table Location A table devoid of primary key index is called heap, and here data is not arranged in a particular order, which gives rise to issues that adversely affect performance. Data must be stored in some kind of order. If we put clustered index on it then the order will be forced by that index and the data will be stored in that particular order. Understanding Table Hints with Examples Hints are options and strong suggestions specified for enforcement by the SQL Server query processor on DML statements. The hints override any execution plan the query optimizer might select for a query. 2010 Data Pages in Buffer Pool – Data Stored in Memory Cache One of my earlier year article, which I still read it many times and point developers to read it again. It is clear from the Resultset that when more than one index is used, datapages related to both or all of the indexes are stored in Memory Cache separately. TRANSACTION, DML and Schema Locks Can you create a situation where you can see Schema Lock? Well, this is a very simple question, however during the interview I notice over 50 candidates failed to come up with the scenario. In this blog post, I have demonstrated the situation where we can see the schema lock in database. 2011 Solution – Puzzle – Statistics are not updated but are Created Once In this example I have created following situation: Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated Auto Update Statistics and Auto Create Statistics for database is TRUE Now I have requested two things in the example 1) Why this is happening? 2) How to fix this issue? Selecting Domain from Email Address This is a straight to script blog post where I explain how to select only domain name from entire email address. Solution – Generating Zero Without using Any Numbers in T-SQL How to get zero digit without using any digit? This is indeed a very interesting question and the answer is even interesting. Try to come up with answer in next 10 minutes and if you can’t come up with the answer the blog post read this post for solution. 2012 Simple Explanation and Puzzle with SOUNDEX Function and DIFFERENCE Function In simple words - SOUNDEX converts an alphanumeric string to a four-character code to find similar-sounding words or names. DIFFERENCE function returns an integer value. The  integer returned is the number of characters in the SOUNDEX values that are the same. Read Only Files and SQL Server Management Studio (SSMS) I have come across a very interesting feature in SSMS related to “Read Only” files. I believe it is a little unknown feature as well so decided to write a blog about the same. Identifying Column Data Type of uniqueidentifier without Querying System Tables How do I know if any table has a uniqueidentifier column and what is its value without using any DMV or System Catalogues? Only information you know is the table name and you are allowed to return any kind of error if the table does not have uniqueidentifier column. Read the blog post to find the answer. Solution – User Not Able to See Any User Created Object in Tables – Security and Permissions Issue Interesting question – “When I try to connect to SQL Server, it lets me connect just fine as well let me open and explore the database. I noticed that I do not see any user created instances but when my colleague attempts to connect to the server, he is able to explore the database as well see all the user created tables and other objects. Can you help me fix it?” Importing CSV File Into Database – SQL in Sixty Seconds #018 – Video Here is interesting small 60 second video on how to import CSV file into Database. ColumnStore Index – Batch Mode vs Row Mode Here is the logic behind when Columnstore Index uses Batch Mode and when it uses Row Mode. A batch typically represents about 1000 rows of data. Batch mode processing also uses algorithms that are optimized for the multicore CPUs and increased memory throughput. Follow up – Usage of $rowguid and $IDENTITY This is an excellent follow up blog post of my earlier blog post where I explain where to use $rowguid and $identity.  If you do not know the difference between them, this is a blog with a script example. 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

    Read the article

  • T-SQL Tuesday #31 - Logging Tricks with CONTEXT_INFO

    - by Most Valuable Yak (Rob Volk)
    This month's T-SQL Tuesday is being hosted by Aaron Nelson [b | t], fellow Atlantan (the city in Georgia, not the famous sunken city, or the resort in the Bahamas) and covers the topic of logging (the recording of information, not the harvesting of trees) and maintains the fine T-SQL Tuesday tradition begun by Adam Machanic [b | t] (the SQL Server guru, not the guy who fixes cars, check the spelling again, there will be a quiz later). This is a trick I learned from Fernando Guerrero [b | t] waaaaaay back during the PASS Summit 2004 in sunny, hurricane-infested Orlando, during his session on Secret SQL Server (not sure if that's the correct title, and I haven't used parentheses in this paragraph yet).  CONTEXT_INFO is a neat little feature that's existed since SQL Server 2000 and perhaps even earlier.  It lets you assign data to the current session/connection, and maintains that data until you disconnect or change it.  In addition to the CONTEXT_INFO() function, you can also query the context_info column in sys.dm_exec_sessions, or even sysprocesses if you're still running SQL Server 2000, if you need to see it for another session. While you're limited to 128 bytes, one big advantage that CONTEXT_INFO has is that it's independent of any transactions.  If you've ever logged to a table in a transaction and then lost messages when it rolled back, you can understand how aggravating it can be.  CONTEXT_INFO also survives across multiple SQL batches (GO separators) in the same connection, so for those of you who were going to suggest "just log to a table variable, they don't get rolled back":  HA-HA, I GOT YOU!  Since GO starts a new batch all variable declarations are lost. Here's a simple example I recently used at work.  I had to test database mirroring configurations for disaster recovery scenarios and measure the network throughput.  I also needed to log how long it took for the script to run and include the mirror settings for the database in question.  I decided to use AdventureWorks as my database model, and Adam Machanic's Big Adventure script to provide a fairly large workload that's repeatable and easily scalable.  My test would consist of several copies of AdventureWorks running the Big Adventure script while I mirrored the databases (or not). Since Adam's script contains several batches, I decided CONTEXT_INFO would have to be used.  As it turns out, I only needed to grab the start time at the beginning, I could get the rest of the data at the end of the process.   The code is pretty small: declare @time binary(128)=cast(getdate() as binary(8)) set context_info @time   ... rest of Big Adventure code ...   go use master; insert mirror_test(server,role,partner,db,state,safety,start,duration) select @@servername, mirroring_role_desc, mirroring_partner_instance, db_name(database_id), mirroring_state_desc, mirroring_safety_level_desc, cast(cast(context_info() as binary(8)) as datetime), datediff(s,cast(cast(context_info() as binary(8)) as datetime),getdate()) from sys.database_mirroring where db_name(database_id) like 'Adv%';   I declared @time as a binary(128) since CONTEXT_INFO is defined that way.  I couldn't convert GETDATE() to binary(128) as it would pad the first 120 bytes as 0x00.  To keep the CAST functions simple and avoid using SUBSTRING, I decided to CAST GETDATE() as binary(8) and let SQL Server do the implicit conversion.  It's not the safest way perhaps, but it works on my machine. :) As I mentioned earlier, you can query system views for sessions and get their CONTEXT_INFO.  With a little boilerplate code this can be used to monitor long-running procedures, in case you need to kill a process, or are just curious  how long certain parts take.  In this example, I added code to Adam's Big Adventure script to set CONTEXT_INFO messages at strategic places I want to monitor.  (His code is in UPPERCASE as it was in the original, mine is all lowercase): declare @msg binary(128) set @msg=cast('Altering bigProduct.ProductID' as binary(128)) set context_info @msg go ALTER TABLE bigProduct ALTER COLUMN ProductID INT NOT NULL GO set context_info 0x0 go declare @msg1 binary(128) set @msg1=cast('Adding pk_bigProduct Constraint' as binary(128)) set context_info @msg1 go ALTER TABLE bigProduct ADD CONSTRAINT pk_bigProduct PRIMARY KEY (ProductID) GO set context_info 0x0 go declare @msg2 binary(128) set @msg2=cast('Altering bigTransactionHistory.TransactionID' as binary(128)) set context_info @msg2 go ALTER TABLE bigTransactionHistory ALTER COLUMN TransactionID INT NOT NULL GO set context_info 0x0 go declare @msg3 binary(128) set @msg3=cast('Adding pk_bigTransactionHistory Constraint' as binary(128)) set context_info @msg3 go ALTER TABLE bigTransactionHistory ADD CONSTRAINT pk_bigTransactionHistory PRIMARY KEY NONCLUSTERED(TransactionID) GO set context_info 0x0 go declare @msg4 binary(128) set @msg4=cast('Creating IX_ProductId_TransactionDate Index' as binary(128)) set context_info @msg4 go CREATE NONCLUSTERED INDEX IX_ProductId_TransactionDate ON bigTransactionHistory(ProductId,TransactionDate) INCLUDE(Quantity,ActualCost) GO set context_info 0x0   This doesn't include the entire script, only those portions that altered a table or created an index.  One annoyance is that SET CONTEXT_INFO requires a literal or variable, you can't use an expression.  And since GO starts a new batch I need to declare a variable in each one.  And of course I have to use CAST because it won't implicitly convert varchar to binary.  And even though context_info is a nullable column, you can't SET CONTEXT_INFO NULL, so I have to use SET CONTEXT_INFO 0x0 to clear the message after the statement completes.  And if you're thinking of turning this into a UDF, you can't, although a stored procedure would work. So what does all this aggravation get you?  As the code runs, if I want to see which stage the session is at, I can run the following (assuming SPID 51 is the one I want): select CAST(context_info as varchar(128)) from sys.dm_exec_sessions where session_id=51   Since SQL Server 2005 introduced the new system and dynamic management views (DMVs) there's not as much need for tagging a session with these kinds of messages.  You can get the session start time and currently executing statement from them, and neatly presented if you use Adam's sp_whoisactive utility (and you absolutely should be using it).  Of course you can always use xp_cmdshell, a CLR function, or some other tricks to log information outside of a SQL transaction.  All the same, I've used this trick to monitor long-running reports at a previous job, and I still think CONTEXT_INFO is a great feature, especially if you're still using SQL Server 2000 or want to supplement your instrumentation.  If you'd like an exercise, consider adding the system time to the messages in the last example, and an automated job to query and parse it from the system tables.  That would let you track how long each statement ran without having to run Profiler. #TSQL2sDay

    Read the article

  • How best to handle ID3D11InputLayout in rendering code?

    - by JohnB
    I'm looking for an elegant way to handle input layouts in my directx11 code. The problem I have that I have an Effect class and a Element class. The effect class encapsulates shaders and similar settings, and the Element class contains something that can be drawn (3d model, lanscape etc) My drawing code sets the device shaders etc using the effect specified and then calls the draw function of the Element to draw the actual geometry contained in it. The problem is this - I need to create an D3D11InputLayout somewhere. This really belongs in the Element class as it's no business of the rest of the system how that element chooses to represent it's vertex layout. But in order to create the object the API requires the vertex shader bytecode for the vertex shader that will be used to draw the object. In directx9 it was easy, there was no dependency so my element could contain it's own input layout structures and set them without the effect being involved. But the Element shouldn't really have to know anything about the effect that it's being drawn with, that's just render settings, and the Element is there to provide geometry. So I don't really know where to store and how to select the InputLayout for each draw call. I mean, I've made something work but it seems very ugly. This makes me thing I've either missed something obvious, or else my design of having all the render settings in an Effect, the Geometry in an Element, and a 3rd party that draws it all is just flawed. Just wondering how anyone else handles their input layouts in directx11 in a elegant way?

    Read the article

  • Diagnosing xmodmap errors

    - by intuited
    I'm getting this error when trying to use xmodmap to get rid of caps lock: $ xmodmap -e 'clear Lock' X Error of failed request: BadValue (integer parameter out of range for operation) Major opcode of failed request: 118 (X_SetModifierMapping) Value in failed request: 0x17 Serial number of failed request: 8 Current serial number in output stream: 8 I'm running xfce on Maverick "10.10" Meercat. This problem did not occur before I added the Keyboard Layouts applet to a panel; before doing that, I was able to run my xmodmap script to swap Esc and CapsLock: !Remap Caps_Lock as Escape remove Lock = Caps_Lock keysym Caps_Lock = Escape It may be relevant that I chose alt-capslock as the keyboard switch combo in the Keyboard Layouts preferences. I've had a similar problem before, on a different machine, running openbox. On that machine, this problem started when I upgraded to Lucid, and has persisted in Maverick (release 10.10). I reported a bug in xorg. However, it remains unclear whether it's really a problem with xorg, or if I'm just doing something wrong with my configuration. Have other people experienced this problem? Can someone shed some light on what's going on here? It seems there are quite a few layers involved, and I don't understand any of them particularly well, so any information would be helpful. update I've discovered that the problem is specifically triggered by adding the Canada layout variant "Multilingual" (ca-multix). If I instead add the variant "Multilingual (first part)", the problem does not occur. I think this will probably end up being a usable workaround, but I don't yet know what the difference between these variants is. I've filed a freedesktop issue, and am commenting on a related ubuntu issue.

    Read the article

  • First requests are painfully slow

    - by winSharp93
    I am running Redmine under IIS using Zoo. Installation was done using the Web Platform Installer and the default configuration has not been touched. However, when using the application, the first requests take very long to complete (sometimes more than one minute). During that time, the ruby.exe causes some CPU load (about 15%). According to the log files, it's mainly the views taking that long to render: Started GET "/redmine/login" for IP at 2012-09-04 09:54:08 +0200 Processing by AccountController#login as HTML Rendered account/login.html.erb within layouts/base (42150.5ms) Completed 200 OK in 43508ms (Views: 43008.5ms | ActiveRecord: 0.0ms) Rendered account/login.html.erb within layouts/base (42435.1ms) Completed 200 OK in 44100ms (Views: 43523.3ms | ActiveRecord: 0.0ms) After the initial delay, further request times are totally acceptable. Any ideas on how to speed up the warmup time?

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >