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MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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In Postgresql, force unique on combination of two columns
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CREATE TABLE someTable (
id serial primary key,
col1 int NOT NULL,
col2 int NOT NULL,
unique (col1, col2)
)
autoincrement is not postgresql. You want a serial.
If col1 and col2 make a unique and can't be null then they make a good primary key:
CREATE TABLE someTab...
Updating packages in Emacs
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165
In order to automatically update the list of packages, only if there is no package list alrea...
How to add /usr/local/bin in $PATH on Mac
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108
export PATH=$PATH:/usr/local/git/bin:/usr/local/bin
One note: you don't need quotation marks...
Create a tar.xz in one command
...ember to man tar :)
tar cfJ <archive.tar.xz> <files>
Edit 2015-08-10:
If you're passing the arguments to tar with dashes (ex: tar -cf as opposed to tar cf), then the -f option must come last, since it specifies the filename (thanks to @A-B-B for pointing that out!). In that case, the...
Increment a database field by 1
...I have a field, of say logins, how would I go about updating that field by 1 within a sql command?
5 Answers
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How to copy yanked text to VI command prompt
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174
try to use
<ctrl+r>"
where " stands for default register.
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Make column not nullable in a Laravel migration
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edited Jul 17 '17 at 21:29
Script_Coded
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