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Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
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How to avoid the “divide by zero” error in SQL?
...rder to avoid a "Division by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/"...
Selecting multiple classes with jQuery
I’ve had a good look and can’t seem to find out how to select all elements matching certain classes in one jQuery selector statement such as this:
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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How do I use the CONCAT function in SQL Server 2008 R2?
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You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
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Xcode iOS project only shows “My Mac 64-bit” but not simulator or device
...duct->Scheme->Edit Scheme...), and for some reason no executable was selected. I chose my app, saved and now I have my simulator and device options back.
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Does a “Find in project…” feature exist in Eclipse IDE?
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1. Ctrl + H
2. Choose File Search for plain text search in workspace/selected projects
For specific expression searches, choose the relevant tab (such as Java Search which allows you to search for specific identifiers)
For whole project search:
3. Scope (in the form section) > Enclosing...
Resharper Alt Enter not working
...g the radio buttons and clicking OK. Then switching back to the previously selected radiobutton.
Edit
Here is how to change/assign keyshort cuts in Visual Studio/Resharper from JetBrains Knowledge Base
The command you are looking for is called "ReSharper_QuickFix". In version 8, this is called "R...
What is the equivalent of 'describe table' in SQL Server?
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use Select * From INFORMATION_SCHEMA.COLUMNS Where TABLE_NAME = 'TABLENAME' if you don't want to use a stored procedure
– Matias Elorriaga
Aug 4 '14 at 18:21
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MySQL skip first 10 results
Is there a way in MySQL to have the first 10 result from a SELECT query skipped?
I'd like it to work something like LIMIT.
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