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What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phon
What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phone.
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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Multiple INSERT statements vs. single INSERT with multiple VALUES
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Addition: SQL Server 2012 shows some improved performance in this area but doesn't seem to tackle the specific issues noted below. This
should apparently be fixed in the next major version after
SQL Server 2012!
Your plan shows t...
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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SQL Server insert if not exists best practice
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I definitely believe this is the right way to go, giving SQL Server the best possible hints for optimizing, in contrast to the sub query approach.
– Mads Nielsen
Mar 3 '16 at 20:48
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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...
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...
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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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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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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