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  • Are conditional subqueries optimized out, if the condition is false?

    - by Tobias Schulte
    I have a table foo and a table bar, where each foo might have a bar (and a bar might belong to multiple foos). Now I need to select all foos with a bar. My sql looks like this SELECT * FROM foo f WHERE [...] AND ($param IS NULL OR (SELECT ((COUNT(*))>0) FROM bar b WHERE f.bar = b.id)) with $param being replaced at runtime. The question is: Will the subquery be executed even if param is null, or will the dbms optimize the subquery out? We are using mysql, mssql and oracle. Is there a difference between these regarding the above?

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  • Where's the rest of the space used in this table?

    - by Eric H.
    I'm using SQL Server 2005. I have a table whose row size should be 124 bytes. It's all ints or floats, no NULL columns (so everything is fixed width). There is only one index, clustered. The fill factor is 0. After inserting a ton of data, sp_spaceused returns the following name rows reserved data index_size unused OHLC_Bar_Trl 117076054 29807664 KB 29711624 KB 92344 KB 3696 KB which shows a rowsize of approx (29807664*1024)/117076054 = 260 bytes/row. Where's the rest of the space? Is there some DBCC command I need to run to tighten up this table (I could not insert the rows in correct index order, so maybe it's just internal fragmentation)?

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  • SQL tables using VARCHAR with UTF8 (with respect to multi byte character length)

    - by Elius
    Like in Oracle VARCHAR( 60 CHAR ) I would like to specify a varchar field with variable length depending on the inserted characters. for example: create table X (text varchar(3)) insert into X (text) VALUES ('äöü') Should be possible (with UTF8 as the default charset of the database). On DB2 I got this Error: DB2 SQL Error: SQLCODE=-302, SQLSTATE=22001 (Character data, right truncation occurred; for example, an update or insert value is a string that is too long for the column, or a datetime value cannot be assigned to a host variable, because it is too small.) I'm looking for solutions for DB2, MsSql, MySql, Hypersonic.

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  • SQL Query taking too long

    - by user345426
    I am trying to optimize the SQL query listed below. It is basically a search engine code that retrieves products based on the products name. It also checks products model number and whether or not it is enabled. This executes in about 1.6 seconds when I run it directly through the phpMyAdmin tool but takes about 3 seconds in total to load in conjunction with the PHP file it is placed in. I need to add a category search functionality and now that is crashing the MySQL server, HELP! SELECT DISTINCT p.products_id , p.products_image , p.products_price , s.specials_new_products_price, p.products_weight , p.products_unit_quantity , pd.products_name , pd.products_img_alt , pd.products_affiliate_url FROM products AS p LEFT JOIN vendors v ON v.vendors_id = p.vendors_id LEFT JOIN specials AS s ON s.products_id = p.products_id AND s.status = 1, categories AS c , products_description AS pd , products_to_categories AS p2c WHERE ( ( pd.products_name LIKE '%cleaning%' AND pd.products_name LIKE '%supplies%' ) OR ( p.products_model LIKE '%cleaning%' AND p.products_model LIKE '%supplies%' ) OR p.products_id = 'cleaning supplies' OR v.vendors_prefix = 'cleaning supplies' OR CONCAT( CAST(v.vendors_prefix AS CHAR), '-', CAST(p.products_id AS CHAR) ) = 'cleaning supplies' ) AND p.products_status = '1' AND c.categories_status = '1' AND p.products_id = pd.products_id AND p2c.products_id = pd.products_id AND p2c.categories_id = c.categories_id ORDER BY pd.products_name

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  • Joining two select queries and ordering results

    - by user1
    Basically I'm just unsure as to why this query is failing to execute: (SELECT replies.reply_post, replies.reply_content, replies.reply_date AS d, members.username FROM (replies) AS a INNER JOIN members ON replies.reply_by = members.id) UNION (SELECT posts.post_id, posts.post_title, posts.post_date AS d, members.username FROM (posts) as b WHERE posts.post_set = 0 INNER JOIN members ON posts.post_by = members.id) ORDER BY d DESC LIMIT 5 I'm getting this error: #1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a INNER JOIN members ON replies.re' at line 2 All I'm trying to do is select the 5 most recent rows (dates) from these two tables. I've tried Join, union etc and I've seen numerous queries where people have put another query after the FROM statement and that just makes no logical sense to me as to how that works? Am I safe to say that you can join the same table from two different but joined queries? Or am I taking completely the wrong approach, because frankly I can't seem see how this query is failing despite reading the error message. (The two queries on there own work fine)

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  • How to get a list of users for all instance's databases

    - by stee1rat
    I guess the procedure should be something like this: declare @db varchar(100) declare @user varchar(100) declare c cursor for select name from sys.sysdatabases open c fetch next from c into @db while @@fetch_status = 0 begin print @db exec ('use ' + @db) declare u cursor for select name from sys.sysusers where issqlrole <> 1 and hasdbaccess <> 0 and isntname <> 1 open u fetch next from u into @user while @@fetch_status = 0 begin print @user fetch next from u into @user end print '--------------------------------------------------' close u deallocate u fetch next from c into @db end close c deallocate c But the problem is that exec ('use ' + @db) doesn't work. And i always get user list of currently chosen database. How should i fix that? P.S.: I want this code to work on both 2000 and 2005 sql servers.

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  • [PersistenceException: org.hibernate.exception.SQLGrammarException: could not execute query]

    - by doniyor
    i need help. i am trying to select from database thru sql statement in play framework, but it gives me error, i cannot figure out where the clue is. here is the code: @Transactional public static Users findByUsernameAndPassword(String username, String password){ String hash = DigestUtils.md5Hex(password); Query q = JPA.em().createNativeQuery("select * from USERS where" + "USERNAME=? and PASSWORD=?").setParameter(1, username).setParameter(2, password); List<Users> users = q.getResultList(); if(users.isEmpty()){ return null; } else{ return users.get(0); here is the eror message: [PersistenceException: org.hibernate.exception.SQLGrammarException: could not execute query] can someone help me please! any help i would appreciate! thanks

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  • Why is my left join not returning nulls?

    - by Griz
    In sql server 2008, I have the following query: select c.title as categorytitle, s.title as subcategorytitle, i.title as itemtitle from categories c join subcategories s on c.categoryid = s.categoryid left join itemcategories ic on s.subcategoryid = ic.subcategoryid left join items i on ic.itemid = i.itemid where (ic.isactive = 1 or ic.isactive is null) and i.siteid = 132 order by c.title, s.title I am trying to get items in their subcategories, but I still want to return a record if there are no items in the category or subcategory. Subcategories that have no items are never returned. What am I doing wrong? Thank you EDIT Modified query with a second left join and where clause, but it's still not returning nulls. :/

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  • ASP.NET Template Selector/Builder - Dynamic CMS

    - by Ugene
    I am currently building my own CMS for various reasons that could take a long to explain... However i am looking for a dynamic solution to create templates for pages within the CMS and all areas must be editable via the administration area, maybe large text areas broken into multiple areas, text and image area on a page etc. Following on from the above i would like to create the following: Create a new page (selecting a pre-defined template like below) http://img525.imageshack.us/img525/9872/nestedpages.png and then upon editing the page it would have created as many text editors required for each editable region or a file upload control for an image area for example. i am thinking of using nested masterpages for the design elements, just unsure the best-practice way to achieve the above (db structure etc) I somehow hope this provides enough information but are happy to answer any questions you may have. Thanks

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  • Automatic form generation software

    - by Jonathan
    Hi! I'm using winforms. I spend a lot of time drawing forms (maybe not a lot, but it is a boring task). To sum up... I want to develop a simple aplication that connect to a sql server database, let the user to select a table, and put the controls in a form for me (generate the designer code), based on the tipe of each column. Then my app will name each control like the column of the table, set the maxlengh property (if the type is varchar), and create a label with the same text near the control. If the column is a FK, then the app will draw a combobox and so on. I saw that Telerik Open ORM make something like this, but I only need a simple app for the IU Generation. If the same day I finish my little application I discover a tool that make the same... I will feel myself stupid :D Are there any tool out there that do this work for me? Thanks

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  • LinqToSql Sub Entiity Multiple And Operators

    - by halit
    Hi I have an Array of Featureset Id , My Vehicles table has got sub table as FeatureSets I wrote Sql Query Like SELECT [t0].[ID] FROM [dbo].[SearchResultView] AS [t0] Join [dbo].[VehicleFeatureSet] AS [t1] on t0.ID = t1.VehicleID where t1.FeatureSetID = 1 and t1.FeatureSetID= 2 and t1.FeatureSetID= 3 I tried. But I Couldn't var features = Request.QueryString["FeatureSets"].Split(',').ToList().ConvertAll(new Converter<string, int>(StrinToint)); IQueryable<SearchResultView> result = db.SearchResultViews.Where(m => m.Active == true); foreach (var featuree in features) { result = result.Where(m => m.VehicleFeatureSets.Any(c => c.FeatureSetID == featuree)); } How Can I write this LINQ Query

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  • comparing two tables

    - by sza
    I have two identical table ie all the columns are identical and one of the datatype is Text, one is varchar(255) and the rest are int. Lets say the table name is 'AAAAA'. Table AAAAA was processed and backed up earlier this month. Both the tables were storing data and now the second table is only storing data. I need to find unmatching records from the second table (BBBBB) which is storing data right now and add those records to Table AAAAA. Your help will be highly appreciated. I tried to use 'EXCEPT' but it does not support text datatype. I'm using SQL Server 2005.

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  • Getting Popular Topics on a Custom Made Forum

    - by Navarr
    For this website we're working on, we're trying to get the most popular topics (based on how many posts have been made in them within the last 24 hours). We have a medium to large based forum, and the current MySQL query looks like this: SELECT `forums_topics`.*, ( SELECT COUNT(`id`) FROM `forums_posts` WHERE `postdate` > (UNIX_TIMESTAMP()-60*60*24) AND `topicid`=`forums_topics`.`id` ) AS `trendy_threads` FROM `forums_topics` WHERE `deleted`=0 ORDER BY `trendy_threads` DESC,`postdate` DESC LIMIT 3 This unfortunately causes an SQL timeout with just one query and Error 500's. How can we get this information as quickly and as efficiently as possible?

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  • Accessing C++ Functions From Text storage

    - by Undawned
    I'm wondering if anyone knows how to accomplish the following: Let's say I have a bunch of data stored in SQL, lets say one of the fields could be called funcName, function name would contain data similar to "myFunction" What I'm wondering is, is there a way I can than in turn extract the function name and actually call that function? There's a few ways I can think of to accomplish this, one is changing funcName to funcId and linking up with an array or similar, but I'm looking for something a bit more dynamic that would allow me to add the data on fly without having to update the actual source code every time I add a call to a new function assuming of course that the function already exists and is accessible via scope location we call it from. Any help would be greatly appreciated.

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  • Application Role and access second database

    - by lszk
    I have written a script to create an audit trails to my database in a second one db. So far I had no problems during tests on my dev machine from SQL Server Management Studio. Problems started to occurs when I first tried to test my triggers from my application by modyfing data in it. Using profiler I found out, that my audit trails db is not visible in sys.databases, so here lies the problem. The application using an Application Role, so as I found on MSDN, that's why I can't get access to other db on the server. I'm not a DBA. I have no experience with properly settings the security stuff, so please guide me, how can I set the setting for guest account (according to MSDN) to get access to this db? I need to have a record for this database in sys.databases and I need to be able to insert data in this database in all tables. No select, update or delete I need.

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  • filter queryset based on list, including None

    - by jujule
    Hi all I dont know if its a django bug or a feature but i have a strange ORM behaviour with MySQL. class Status(models.Model): name = models.CharField(max_length = 50) class Article(models.Model) status = models.ForeignKey(status, blank = True, null=True) filters = Q(status__in =[0, 1,2] ) | Q(status=None) items = Article.objects.filter(filters) this returns Article items but some have other status than requested [0,1,2,None] looking at the sql query : SELECT [..] FROM `app_article` LEFT OUTER JOIN `app_status` ON (`app_article`.`status_id` = `app_status`.`id`) WHERE (`app_article`.`status_id` IN (1, 2) OR `app_status`.`id` IS NULL) ORDER BY [...] the OR app_status.id IS NULL part seems to be the cause. if i change it to OR app_article.status_id IS NULL it works correctly. How to deal with this ? Thanx.

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  • C# SQL SELECT Statement

    - by Feren6
    I have the following code: SqlCommand cmd2 = new SqlCommand("SELECT ClaimId FROM tblPayment WHERE PaymentId = " + PaymentID.ToString(), mvarDBConn); SqlDataReader reader = cmd2.ExecuteReader(); reader.Read(); Int32 ClaimId = reader.GetInt32(0); reader.Close(); If I run the SELECT statement in SQL it returns the number fine, but when I use ExecuteReader all it returns is 0. I've tried multiple methods including ExecuteScalar, ExecuteNonQuery, reader.GetString then casting that to an int, etc. What am I missing? Thanks.

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  • SQL Database application written in Visual Basic in Visual Studio 2010

    - by TID
    Hello, I am writing a program and part of it is to store the keyed entry in a database on an sql server when the enter key is hit. The database is small and simple with only three entry spots in the table. one for the tracking number, one for the date entered, and one for the time entered. The only thing the user will see is the tracking number text box and an enter button. the date and time will be auto entered when the enter key is hit. i am relatively new to databases so i cannot figure out how to send the data to the database. The database is already configured, just need to get the program and the database talking to eachother. Thanks.

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  • Is it possible to inspect the contents of a Table Value Parameter via the debugger?

    - by Stephen Edmonds
    Does anyone know if it is possible to use the Visual Studio / SQL Server Management Studio debugger to inspect the contents of a Table Value Parameter passed to a stored procedure? To give a trivial example: CREATE TYPE [dbo].[ControllerId] AS TABLE( [id] [nvarchar](max) NOT NULL ) GO CREATE PROCEDURE [dbo].[test] @controllerData [dbo].[ControllerId] READONLY AS BEGIN SELECT COUNT(*) FROM @controllerData; END DECLARE @SampleData as [dbo].[ControllerId]; INSERT INTO @SampleData ([id]) VALUES ('test'), ('test2'); exec [dbo].[test] @SampleData; Using the above with a break point on the exec statement, I am able to step into the stored procedure without any trouble. The debugger shows that the @controllerData local has a value of '(table)' but I have not found any tool that would allow me to actual view the rows that make up that table.

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  • Fulltext search not returning expected results

    - by Puneet
    I am experimenting with SQL Server full text search. I have a simple Categories table with Id as the primary key: CREATE TABLE [dbo].[Category]( [Id] [int] IDENTITY(1,1) NOT NULL, [CategoryName] [varchar](100) NOT NULL, ) My Query is: SELECT * FROM FREETEXTTABLE (Category, CategoryName, 'music') AS F INNER JOIN Category C ON F.[Key] = C.Id ORDER BY F.Rank DESC This returns me several records with the word music in them, but it does NOT return any record with word ‘musical’. Although, it can be said that the string being searched is not very big and using the LIKE operator will resolve it. I would like to use fulltext search because this simple example is going to be extended to include other tables and fileds.

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  • Generating incremental numeric column values during INSERT SELECT statement

    - by Charles
    I need to copy some data from one table to another in Oracle, while generating incremental values for a numeric column in the new table. This is a once-only exercise with a trivial number of rows (100). I have an adequate solution to this problem but I'm curious to know if there is a more elegant way. I'm doing it with a temporary sequence, like so: CREATE SEQUENCE temp_seq START WITH 1; INSERT INTO new_table (new_col, copied_col1, copied_col2) SELECT temp_seq.NEXTVAL, o.* FROM (SELECT old_col1, old_col2 FROM old_table) o; DROP SEQUENCE temp_seq; Is there way to do with without creating the sequence or any other temporary object? Specifically, can this be done with a self-contained INSERT SELECT statement? There are similar questions, but I believe the specifics of my question are original to SO.

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  • Username correct, password incorrect?

    - by jonnnnnnnnnie
    In a login system, how can you tell if the user has entered the password incorrectly? Do you perform two SQL queries, one to find the username, and then one to find the username and matching (salted+hashed etc) password? I'm asking this because If the user entered the password incorrectly, I want to update the failed_login_attempts column I have. If you perform two queries wouldn't that increase overhead? If you did a query like this, how would you tell if the password entered was correct or not, or whether the username doesn't exist: SELECT * FROM author WHERE username = '$username' AND password = '$password' LIMIT 1 ( ^ NB: I'm keeping it simple, will use hash and salt, and will sanitize input in real one.) Something like this: $user = perform_Query() // get username and password? if ($user['username'] == $username && $user['password'] == $password) { return $user; } elseif($user['username'] == $username && $user['password'] !== $password) { // here the password doesn't match // update failed_login_attemps += 1 }

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  • Computed Column with relationships

    - by Sethery
    I have a table, MapLocation, which has a column and two relationships with tables that have a field that really need to be displayed as a single concatenated value. I was thinking this was a perfect case for a computed column, but not sure how to go about it. MapLocation MaoNo Section _____________________ _____________________ _____________________ MapNoId MapNoId SectionId SectionId MapNumber (int) Section (int) Identifier (nvarchar) LocationName (nvarchar) LocationName = "MapNUmber - SectionNumber - Identifier" ex: 20 - 03 - SW4 How would I write that? I haven't done much with computed columns or concatenating in SQL. Edit: I need an actual computed column that is automatically updated, im looking for the formula. Or is this more of a function/trigger? Its possible, I certainly barely know what I'm doing. The idea is that I dont want to have to do two more server calls and concatenate these values client side.

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  • WebSQL Databases between two different pages?

    - by Srikanth Rayabhagi
    Is there any particular way in which we can access the Web SQL Database of one page, by other page. To make it more clear, suppose a.com creates the database DB and store some info. Now b.com comes and want to access the same database DB. Is there a way? Or are there any alternatives to do this? I tried to implement in HTML5 and Javascript but the databases as well as the localStorages are confining only to particular pages, I want this to be cross the pages.

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  • Which file types are worth compressing (zipping) for remote storage? For which of them the compresse

    - by user193655
    I am storing documents in sql server in varbinary(max) fileds, I use filestream optionally when a user has: (DB_Size + Docs_Size) ~> 0.8 * ExpressEdition_Max_DB_Size I am currently zipping all the files, anyway this is done because the Document Read/Write work was developed 10 years ago where Storage was more expensive than now. Many files when zipped are almost as big as the original (a zipped pdf is about 95% of original size). And anyway unzipping has some overhead, that becomes twice when I need also to "Check-in"/Update the file because I need to zip it. So I was thinking of giving to the users the option to choose whether the file type will be zipped or not by providing some meaningful default values. For my experience I would impose the following rules: 1) zip by default: txt, bmp, rtf 2) do not zip by default: jpg, jpeg, Microsoft Office files, Open Office files, png, tif, tiff Could you suggest other file types chosen among the most common or comment on the ones I listed here?

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