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WHERE vs HAVING
...as number") after HAVING and not WHERE in MySQL?
WHERE is applied before GROUP BY, HAVING is applied after (and can filter on aggregates).
In general, you can reference aliases in neither of these clauses, but MySQL allows referencing SELECT level aliases in GROUP BY, ORDER BY and HAVING.
And...
How to replace captured groups only?
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The parenthesis are used to create "groups", which then get assigned a base-1 index, accessible in a replace with a $, so the first word (\w+) is in a group, and becomes $1, the middle part (\d+) is the second group, (but gets ignored in the replace), and the t...
Apply multiple functions to multiple groupby columns
The docs show how to apply multiple functions on a groupby object at a time using a dict with the output column names as the keys:
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How to output only captured groups with sed?
Is there any way to tell sed to output only captured groups? For example given the input:
8 Answers
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Count number of records returned by group by
How do I count the number of records returned by a group by query,
13 Answers
13
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
prog
command ...
iOS 7 parallax effect in my view controller
... = @(-10);
horizontalMotionEffect.maximumRelativeValue = @(10);
// Create group to combine both
UIMotionEffectGroup *group = [UIMotionEffectGroup new];
group.motionEffects = @[horizontalMotionEffect, verticalMotionEffect];
// Add both effects to your view
[myBackgroundView addMotionEffect:group];
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What's the best way to send a signal to all members of a process group?
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You don't say if the tree you want to kill is a single process group. (This is often the case if the tree is the result of forking from a server start or a shell command line.) You can discover process groups using GNU ps as follows:
ps x -o "%p %r %y %x %c "
If it is a process gr...
Mark error in form using Bootstrap
...en
<div class="container">
<form>
<div class="form-group row">
<label for="inputEmail" class="col-sm-2 col-form-label text-success">Email</label>
<div class="col-sm-7">
<input type="email" class="form-control is-valid" id="inputEmai...
MySQL/SQL: Group by date only on a Datetime column
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Cast the datetime to a date, then GROUP BY using this syntax:
SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY Dat...