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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
... @jpmc26 «If you want to let PostgreSQL generate the index name» You mean the constraint name?
– tuxayo
Sep 6 '17 at 8:43
4
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Remove duplicate rows in MySQL
...de the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
This will drop all the duplicate rows. As an added benefit, future INSERTs that are duplicates will error out. As always, you may want to take a backup before running something like thi...
How can I merge two commits into one if I already started rebase?
...Summary
The error message
Cannot 'squash' without a previous commit
means you likely attempted to “squash downward.” Git always squashes a newer commit into an older commit or “upward” as viewed on the interactive rebase todo list, that is into a commit on a previous line. Changing th...
Intersection of two lists in Bash
...ag the name of the person you are replying to, otherwise it is assumed you mean me.
– Benubird
Feb 23 '15 at 8:34
@nit...
List tables in a PostgreSQL schema
...ouble quotes, all regular expression special characters lose their special meanings and are matched literally. Also, the regular expression special characters are matched literally in operator name patterns (i.e., the argument of \do).
...
How to select where ID in Array Rails ActiveRecord without exception
When I have array of ids, like
6 Answers
6
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How to calculate cumulative normal distribution?
...ormal interval lies within two standard deviations, centered on a standard mean of zero.
If you need the inverse CDF:
>>> norm.ppf(norm.cdf(1.96))
array(1.9599999999999991)
share
|
impro...
How to do this in Laravel, subquery where in
...
Consider this code:
Products::whereIn('id', function($query){
$query->select('paper_type_id')
->from(with(new ProductCategory)->getTable())
->whereIn('category_id', ['223', '15'])
->where('active',...
How to drop column with constraint?
....default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJECT_ID('tbloffers')
AND c.name = N'checkin'
IF @@ROWCOUNT = 0 BREAK
EXEC (@sql)
END
...
What is external linkage and internal linkage?
...
As dudewat said external linkage means the symbol (function or global variable) is accessible throughout your program and internal linkage means that it's only accessible in one translation unit.
You can explicitly control the linkage of a symbol by using ...