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Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?
...lass Person
has_many :dogs
end
d = Dog.new
d.build_person(:attributes => "go", :here => "like normal")
or even
t = Tag.new
t.build_dog(:name => "Rover", :breed => "Maltese")
You can also use create_dog to have it saved instantly (much like the corresponding "create" method you c...
how to check and set max_allowed_packet mysql variable [duplicate]
... 'user', 'pass', 'dbname' );
// to get the max_allowed_packet
$maxp = $db->query( 'SELECT @@global.max_allowed_packet' )->fetch_array();
echo $maxp[ 0 ];
// to set the max_allowed_packet to 500MB
$db->query( 'SET @@global.max_allowed_packet = ' . 500 * 1024 * 1024 );
So if you've got a qu...
IF statement: how to leave cell blank if condition is false (“” does not work)
...pply the if statement to a whole row, and then I would like to use Go To -> Special -> Blanks to delete the blank cells from the row, i.e. the cells for which the condition was false. However, the Go to doesn't detect any blank cells in my row, specifically due to this problem that my IF state...
Calculate total seconds in PHP DateInterval
...pare the time stamps instead?
$now = new DateTime('now');
$diff = $date->getTimestamp() - $now->getTimestamp()
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How to get a random number in Ruby
...s, you can initialize them with:
10.times.map{ 20 + Random.rand(11) }
#=> [26, 26, 22, 20, 30, 26, 23, 23, 25, 22]
Note:
Using Random.new.rand(20..30) (using Random.new) generally would not be a good idea, as explained in detail (again) by Marc-André Lafortune, in his answer (again).
But ...
MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
...
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_field must be in the select, because otherwise the having clause will give an error, but I'm not 100% sure
Never use IN with a subquery; this is notoriously slow.
Only ever use IN with a fixed li...
Eclipse: Files opened by multiple searches using same editor tab
...
Disable the option
Preferences > General > Search > Reuse editors to show matches
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Search all the occurrences of a string in the entire project in Android Studio
...d class, method or field usage.
Alternatively, you can use the
Edit > Find > Find in path…
dialog, which allows you to search the whole workspace.
Also in IDEA 13 there is an awesome "Search Everywhere" option, by default called by double Shift. It allows you to search in project, f...
Ignore python multiple return value
...
It doesn't call the function multiple times: >>> def test(): ... print "here" ... return 1,2,3 ... >>> a,b = test()[:2] here [edit: sorry that code didn't come through, aparently you only get one line in comments. For those not familiar >&g...
Batch File; List files in directory, only filenames?
...
Is OK for me :) dir /b /a-d > tmp.txt
– Stéphane GRILLON
Dec 27 '16 at 21:16
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