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How to insert a newline in front of a pattern?
...adability - the only caveat is that you then need to double all literal \ chars.
– mklement0
Nov 30 '15 at 3:59
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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quick random row selection in Postgres
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You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor he...
In Ruby, is there an Array method that combines 'select' and 'map'?
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I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils.
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}
=> [3, 3, 3, nil, nil, nil]
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}.compact
=> ...
Getting value of select (dropdown) before change
The thing I want to achieve is whenever the <select> dropdown is changed I want the value of the dropdown before change. I am using 1.3.2 version of jQuery and using on change event but the value I am getting over there is after change.
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How can you zip or unzip from the script using ONLY Windows' built-in capabilities?
...e, thanks, just what I was looking for... FYI - I had to remove the minus char in DOS... e.g. jar cMf target.zip sourceDir
– mlo55
Dec 9 '15 at 0:24
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How to check if a string contains only digits in Java [duplicate]
...ves you the actual result: \d
References:
Java Regular Expressions
Java Character Escape Sequences
Edit: due to some confusion in other answers, I am writing a test case and will explain some more things in detail.
Firstly, if you are in doubt about the correctness of this solution (or other...
Create a unique number with javascript time
...oString(36) + Math.random().toString(36).substr(2) That will give you a 19 character alphanumeric string which is a decent amount of entropy. Albeit half of it is predictable.
– Erik Pukinskis
Jul 30 '17 at 23:32
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How can I send an inner to the bottom of its parent ?
...main sticking points: no set heights, must be completely fluid (not enough chars to explain why display: table was not working). This handled everything beautifully; the images inside the div are also flipped when this happens so I just used the class on those elements to flip them back. Looks exac...
Changing selection in a select with the Chosen plugin
I'm trying to change the currently selected option in a select with the Chosen plugin.
4 Answers
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