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Profiling Django
...I didn't realize how much slower the Debug Toolbar made things process. My sql queries were small (30ms) but cpu time was very high (800ms). Another page i was tuning had sql times of 300ms, and cpu time of 8000ms - so i kept trying to find the source of the problem. Turning Django Toolbar off sped ...
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...
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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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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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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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...
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...
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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马云：互联网时代已经过去20年，接下来30年才是关键 - 资讯 - 清泛网 - 专...
...正的机会。所谓现在提出互联网+，还有一个就是互联网如何变成一种应用。未来的时代，更多的靠知识，更多靠的是你的勇气，更多靠你的坚韧不拔去努力。所以我觉得，未来的30年，我们这些人，肯定不行了，那时候我是后来...