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how to exclude null values in array_agg like in string_agg using postgres?
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Thanks. But if the main query (s) returns a 1000 rows, then the 2 subqueries (using unnest) will run once for each row.. Will it be better to tolerate NULLs than executing 2000 extra select queries ?
– Daud
Oct 29 '12 at 17:07
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Uncatchable ChuckNorrisException
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jtahlbornjtahlborn
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ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
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edited May 23 at 21:00
answered Feb 9 '14 at 15:18
Ra...
rreplace - How to replace the last occurrence of an expression in a string?
...> rreplace(s, '2', ' ', 4)
'1 3 4 5'
>>> rreplace(s, '2', ' ', 0)
'1232425'
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Coffeescript — How to create a self-initiating anonymous function?
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160
While you can just use parentheses (e.g. (-> foo)(), you can avoid them by using the do keywo...
Non-recursive depth first search algorithm
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biziclopbiziclop
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WPF Blurry fonts issue- Solutions
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Technical background
There is a in-depth article about WPF Text rendering from one of the WPF ...
Hashing a string with Sha256
...spx
If you inspect your bytes array, you'll see that every second byte is 0x00 (because of the double-wide encoding).
You should be using Encoding.UTF8.GetBytes instead.
But also, you will see different results depending on whether or not you consider the terminating '\0' byte to be part of the d...
How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
...d.)
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General rule: quote it if it can either be empty or contain spaces (or any whitespace really) or...