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Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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best way to add license section to iOS settings bundle
...save it to the root of your project.
Expand the Settings.bundle group and select Root.plist. You will need to add a new section where its key will be Preference Items of type Array. Add the following information:
The Filename key points to the plist that was created by this script. You can cha...
Copy tables from one database to another in SQL Server
... server? Use three part naming.
INSERT INTO bar..tblFoobar( *fieldlist* )
SELECT *fieldlist* FROM foo..tblFoobar
This just moves the data. If you want to move the table definition (and other attributes such as permissions and indexes), you'll have to do something else.
...
Why .NET String is immutable? [duplicate]
...f the string class is. Strings don't have to be implemented as an array of chars, its wholly possible to implement strings as immutable ropes which have the interesting property of O(1) concats and O(lg n) substrings.
– Juliet
Aug 7 '10 at 0:19
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Cannot open database “test” requested by the login. The login failed. Login failed for user 'xyz\ASP
..., rather than not set up as a login.
To test if it's set up as a login
SELECT SUSER_ID('xyz\ASPNET') -- (**not** SUSER_SID)
If NULL
CREATE LOGIN [xyz\ASPNET] FROM WINDOWS
If not NULL
USE test
GO
SELECT USER_ID('xyz\ASPNET')
If NULL
USE test
GO
CREATE USER [xyz\ASPNET] FROM LOGIN [xyz\AS...
In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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OSX - How to auto Close Terminal window after the “exit” command executed.
...
in Terminal.app
Preferences > Profiles > (Select a Profile) > Shell.
on 'When the shell exits' chosen 'Close the window'
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What does collation mean?
... is a correctly ordered list:
Namibia
número
ñandú
ñú
obra
ojo
By selecting the correct collation, you get all this done for you, automatically :-)
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How to auto-remove trailing whitespace in Eclipse?
...rences -> Java -> Editors -> Save Actions -> check Perform the selected actions on save -> check Additional actions -> click Configure.. -> go to Code organizing tab -> check Remove trailing whitespace -> select All lines.
Removing whitespace only from the lines I change...
IntelliJ does not show project folders
...next button which takes you to the Content root. Find your root folder and select it
Click the "ok" button
Ignore any warning that says the name is already in use
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