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How to use count and group by at the same select statement
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needs alias otherwise wouldnt work in mysql. select count(*) from( ) agr
– amas
Jan 9 '14 at 6:54
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Why are joins bad when considering scalability?
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...except in MySQL, which seems to have performance problems with large numbers of joins regardless of how your indexes look. Or at least it has in the past.
– Powerlord
Apr 12 '10 at 17:53
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Using vagrant to run virtual machines with desktop environment
...etter experience, I recommend these improvements:
Don't start the GUI as root. You really want to stay the vagrant user. To do this you need to permit anyone to start the GUI: sudo vim /etc/X11/Xwrapper.config and edit it to allowed_users=anybody.
Next, install the VirtualBox guest tools before st...
Navigation bar appear over the views with new iOS7 SDK
...aque. Rather than doing this in code, simply untick "Translucent" for your root navigation bar:
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Flat file databases [closed]
...te. It works as a database, uses SQL, and is pretty easy to change over to MySQL (especially if you're using abstracted classes for database manipulation like I do!)
In fact, especially with the "accepted answer"'s method, it can drastically cut the memory usage of your app (you don't have to load a...
Stopping an Android app from console
...s adb shell kill
That will only work for devices/emulators where you have root immediately upon running a shell. That can probably be refined slightly to call su beforehand.
Otherwise, you can do (manually, or I suppose scripted):
pc $ adb -d shell
android $ su
android # ps
android # kill <pro...
ORA-00979 not a group by expression
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@AaronDigulla That's what MySQL does, and the world didn't end :p
– Chris Baker
Aug 27 '14 at 21:32
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Getting the location from an IP address [duplicate]
...g JavaScript for client-side scripting, PHP for server-side scripting, and MySQL for the database.
23 Answers
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Add primary key to existing table
...primary key for sql table.
First, you have to drop your old primary key.
MySQL:
ALTER TABLE Persion
DROP PRIMARY KEY;
SQL Server / Oracle / MS Access:
ALTER TABLE Persion
DROP CONSTRAINT 'constraint name';
You have to find the constraint name in your table. If you had
given constraint n...
Mac zip compress without __MACOSX folder?
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To apply to all zip files under some root: find ~ -type f -name '*.zip' -exec zip -d '{}' __MACOSX/\* \;. Substitute your starting point for ~.
– Chris Johnson
Jun 27 '17 at 12:05
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