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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.
...
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...
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\""
share
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VC菜单命令详解(文件打开、保存与关闭) - C/C++ - 清泛网 - 专注C/C++及内核技术
...构造the main frame对象和the main frame window，但不显示它，它包括IDR_MAINFRAME、the toolbar、the status bar；
3、构造view对象和view窗口，但不显示它；
4、建立the document、main frame、view对象之间的关系，这里要借助AddDocTemplate建立的类关系...
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" />
...
Select columns from result set of stored procedure
...
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...
SQLite add Primary Key
I created a table in Sqlite by using the CREATE TABLE AS syntax to create a table based on a SELECT statement. Now this table has no primary key but I would like to add one.
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How can I get the actual stored procedure line number from an error message?
When I use SQL Server and there's an error, the error message gives a line number that has no correlation to the line numbers in the stored procedure. I assume that the difference is due to white space and comments, but is it really?
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