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SCOPE_IDENTITY() for GUIDs?
...s an equivalent of SCOPE_IDENTITY() when using GUIDs as a primary key in SQL Server?
5 Answers
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ALTER DATABASE failed because a lock could not be placed on database
...t the problem has occurred elsewhere.
http://www.geakeit.co.uk/2010/12/11/sql-take-offline-fails-alter-database-failed-because-a-lock-could-not-error-5061/
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
...ly recommend not to do is use the GUID column as the clustering key, which SQL Server does by default, unless you specifically tell it not to.
You really need to keep two issues apart:
the primary key is a logical construct - one of the candidate keys that uniquely and reliably identifies every r...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ery frequently asked question here is how to do an upsert, which is what MySQL calls INSERT ... ON DUPLICATE UPDATE and the standard supports as part of the MERGE operation.
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Find all records which have a count of an association greater than zero
...inct.size
=> 17
[14] pry(main)> Article.joins(:comments).distinct.to_sql
=> "SELECT DISTINCT \"articles\".* FROM \"articles\" INNER JOIN \"comments\" ON \"comments\".\"article_id\" = \"articles\".\"id\""
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Search of table names
...DBName.sys.tables
WHERE Name LIKE '%XXX%'
If so, you could use dynamic SQL to add the dbname to the query:
DECLARE @DBName NVARCHAR(200) = 'YourDBName',
@TableName NVARCHAR(200) = 'SomeString';
IF NOT EXISTS (SELECT 1 FROM master.sys.databases WHERE Name = @DBName)
BEGIN
PR...
Targeting both 32bit and 64bit with Visual Studio in same solution/project
...istered in the GAC, you can also use the standard reference tags this way (SQLite as an example):
<ItemGroup Condition="'$(Platform)' == 'x86'">
<Reference Include="System.Data.SQLite, Version=1.0.80.0, Culture=neutral, PublicKeyToken=db937bc2d44ff139, processorArchitecture=x86" />
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Socket 错误返回码详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...IX作業系統,這個錯誤的意思是指欲開啟檔案的路徑名稱(包括檔案名稱)太長。
WSAEHOSTDOWN (10064) 對方主機關閉
在柏克萊socket介面的解釋中,這個錯誤發生的原因是當遠端主機關閉或系統出問題。
WSAEHOSTUNREACH (10065) 無法聯...
Select columns from result set of stored procedure
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This was interesting: sqlnerd.blogspot.com/2005/09/…
– d-_-b
Mar 4 '12 at 23:40
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Does the join order matter in SQL?
... In fact, all join types are associative, as specified by the SQL standard and according to mathematical definitions of associativity, but they don't appear associative because rearranging the parentheses requires moving the ON clause (i.e. the "join specification") to a new location. T...