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Rails 3: Get Random Record
...ffset(rand(Thing.count)).first
Actually, in Rails 3 all examples will work. But using order RANDOM is quite slow for big tables but more sql-style
UPD. You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select ma...
Java exception not caught?
...
From the Java Language Specification 14.20.2.:
If the catch block completes abruptly for reason R, then the finally block is executed. Then there is a choice:
If the finally block completes normally, then the try statement completes abruptly for reason R.
If the finally block completes ...
Can you use if/else conditions in CSS?
I would like to use conditions in my CSS.
16 Answers
16
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Powershell v3 Invoke-WebRequest HTTPS error
Using Powershell v3's Invoke-WebRequest and Invoke-RestMethod I have succesfully used the POST method to post a json file to a https website.
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Do we need semicolon at the end? [duplicate]
...
The concept is known as JavaScript Semicolon Insertion or "Automatic Semicolon Insertion". This blog post: JavaScript Semicolon Insertion: Everything you need to know outlines the concept well in an understandable manner using examples und...
How does one unit test routes with Express?
...of learning Node.js and have been playing around with Express . Really like the framework;however, I'm having trouble figuring out how to write a unit/integration test for a route.
...
How should I validate an e-mail address?
...mails addresses that conform to RFC 2822, (and will still fail on things like "user@gmail.com.nospam", as will org.apache.commons.validator.routines.EmailValidator)
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\...
What does the “assert” keyword do? [duplicate]
...reported" means that an AssertionError is thrown.
And finally, a lesser known feature of assert:
You can append : "Error message" like this:
assert d != null : "d is null";
to specify what the error message of the thrown AssertionError should be.
This post has been rewritten as an article ...
Convert RGB to RGBA over white
...an as-transparent-as-possible rgba color (when displayed over white). Make sense? I'm looking for an algorithm, or at least idea of an algorithm for how to do so.
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How to export/import PuTTy sessions list?
...xe, require elevated prompt:
Only sessions:
regedit /e "%USERPROFILE%\Desktop\putty-sessions.reg" HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions
All settings:
regedit /e "%USERPROFILE%\Desktop\putty.reg" HKEY_CURRENT_USER\Software\SimonTatham
Powershell:
Only sessions:
reg export H...