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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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select <column> from <table> group by 1 having count(*) > 1; will give a report on duplicated values.
– Jasen
Aug 26 '16 at 22:57
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is of a type that is invalid for use as a key column in an index
...ey nvarchar(max)
)
RETURNS bit
AS
BEGIN
declare @res bit
if exists(select * from key_value where [key] = @key)
set @res = 0
else
set @res = 1
return @res
END
But note that a native index is more performant than a check constraint so unless you really can't specify ...
How do I put a border around an Android textview?
...droid's <layer-list>
How to make bottom border in drawable shape XML selector?
Create borders on a android view in drawable xml, on 3 sides?
Using a 9-patch
You can just make a 9-patch image with a single border. Everything else is the same as discussed above.
Using a View
This is kind of...
Should I put input elements inside a label element?
...he first example given here by superUntitled for textboxes, textareas, and selects. But for radio buttons and checkboxes, I usually use the third example, where I want the input before the accompanying text and don't want the same kind of fixed width and/or floating that the rest of the labels and f...
Git merge master into feature branch
...mment below won't be particularly helpful: I don't control which answer is selected, only @theomega does.
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When to use CouchDB over MongoDB and vice versa
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Ask this questions yourself? And you will decide your DB selection.
Do you need master-master? Then CouchDB. Mainly CouchDB supports master-master replication which anticipates nodes being disconnected for long periods of time. MongoDB would not do well in that environment.
Do yo...
NodeJS - Error installing with NPM
...n 2: Install Visual Studio 2015 (or modify an existing installation) and select Common Tools for Visual C++ during setup. This also works with the free Community and Express for Desktop editions.
???? [Windows Vista / 7 only] requires .NET Framework 4.5.1
Launch cmd, npm config set msvs...
Why are C character literals ints instead of chars?
...;
void print(char);
print('a');
You would expect that the call to print selects the second version taking a char. Having a character literal being an int would make that impossible. Note that in C++ literals having more than one character still have type int, although their value is implementatio...
How to get a variable name as a string in PHP?
...bug_backtrace();
// read file
$file = file($bt[0]['file']);
// select exact print_var_name($varname) line
$src = $file[$bt[0]['line']-1];
// search pattern
$pat = '#(.*)'.__FUNCTION__.' *?\( *?(.*) *?\)(.*)#i';
// extract $varname from match no 2
$var = preg_replace...
How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?
...ysqldump fare with large databases in terms of performance? Any way to use SELECT INTO OUTFILE and LOAD DATA smoothly in your suggested process? (Since they generally perform faster)
– Ifedi Okonkwo
Jul 12 '16 at 19:35
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