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Random record in ActiveRecord
...e current record count) as an offset.
offset = rand(Model.count)
# Rails 4
rand_record = Model.offset(offset).first
# Rails 3
rand_record = Model.first(:offset => offset)
To be honest, I've just been using ORDER BY RAND() or RANDOM() (depending on the database). It's not a performance issue ...
How to extract the year from a Python datetime object?
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4 Answers
4
Active
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How to get distinct values for non-key column fields in Laravel?
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answered Aug 10 '14 at 13:08
Marcin NabiałekMarcin Nabiałek
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How to validate phone numbers using regex
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42 Answers
42
Active
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How to merge two arrays in JavaScript and de-duplicate items
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answered Oct 18 '09 at 8:42
LiraNunaLiraNuna
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Iterate a list as pair (current, next) in Python
...ators:
def threes(iterator):
"s -> (s0,s1,s2), (s1,s2,s3), (s2, s3,4), ..."
a, b, c = itertools.tee(iterator, 3)
next(b, None)
next(c, None)
next(c, None)
return zip(a, b, c)
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Sqlite primary key on multiple columns
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824
According to the documentation, it's
CREATE TABLE something (
column1,
column2,
column3...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
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Matthew
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answered Feb 24 '12 at 22:14
Allen PikeAllen Pike
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How to reference constants in EL?
...a EE 7 container server as early versions had bugs in this. E.g. GlassFish 4.0 and Tomcat 8.0.0-1x fails, but GlassFish 4.1+ and Tomcat 8.0.2x+ works. And you need to make absolutely sure that your web.xml is declared conform the latest servlet version supported by the server. Thus with a web.xml wh...
ADB Install Fails With INSTALL_FAILED_TEST_ONLY
...vice first.
$ adb push bin/hello.apk /tmp/
5210 KB/s (825660 bytes in 0.154s)
$ adb shell pm install /tmp/hello.apk
pkg: /tmp/hello.apk
Failure [INSTALL_FAILED_TEST_ONLY]
$ adb shell pm install -t /tmp/hello.apk
pkg: /tmp/hello.apk
Success
I was able to reproduce the same issue and th...