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how to exclude null values in array_agg like in string_agg using postgres?
... non_canonical_users
FROM groups g
GROUP BY g.id
) s
Or, simpler and may be cheaper, using array_to_string which eliminates nulls:
SELECT
g.id,
array_to_string(
array_agg(CASE WHEN g.canonical = 'Y' THEN g.users ELSE NULL END)
, ','
) canonical_users,
array...
Git copy file preserving history [duplicate]
... confusing question in Git.
Lets say, I have a file dir1/A.txt committed and git preserves a history of commits
7 Answers...
Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...
jquery input select all on focus
I'm using this code to try and select all of the text in the field when a user focuses on the field. What happens is, it selects all for a second, then its unselected and the typing cursor is left where I clicked...
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BCL (Base Class Library) vs FCL (Framework Class Library)
...y that, the base. It contains basic, fundamental types like System.String and System.DateTime.
The Framework Class Library (FCL) is the wider library that contains the totality: ASP.NET, WinForms, the XML stack, ADO.NET and more. You could say that the FCL includes the BCL.
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Find the closest ancestor element that has a specific class
... Still not supported in the current versions of Internet Explorer, Edge and Opera Mini.
– kleinfreund
Nov 12 '15 at 16:55
1
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Coding Conventions - Naming Enums
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Enums are classes and should follow the conventions for classes. Instances of an enum are constants and should follow the conventions for constants. So
enum Fruit {APPLE, ORANGE, BANANA, PEAR};
There is no reason for writing FruitEnum any ...
How to sort git tags by version string order of form rc-X.Y.Z.W?
When I enter a command:
7 Answers
7
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Why does document.querySelectorAll return a StaticNodeList rather than a real Array?
...n't just do document.querySelectorAll(...).map(...) even in Firefox 3.6, and I still can't find an answer, so I thought I'd cross-post on SO the question from this blog:
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When should I use semicolons in SQL Server?
While checking some code on the web and scripts generated by SQL Server Management Studio I have noticed that some statements are ended with a semicolon.
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