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What is causing ERROR: there is no unique constraint matching given keys for referenced table?
...R: there is no unique constraint matching given keys for referenced table, and having stared at it for while now I can't figure out why this error arises in this situation.
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How can I capture the result of var_dump to a string?
...Inwdr I've only ever used var_dump as a convenience feature for debugging, and have certainly never left var_dump statements in production code. I imagine this is typical. In those circumstances, performance is unlikely to be at all relevant.
– Mark Amery
Feb 2...
Are Duplicate HTTP Response Headers acceptable?
...ication about whether duplicate HTTP response headers are allowed by the standard, but I need to know if this will cause compatibility issues.
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Storing SHA1 hash values in MySQL
...d just waste an additional byte for the length of the fixed-length field.
And I also wouldn’t store the value the SHA1 is returning. Because it uses just 4 bit per character and thus would need 160/4 = 40 characters. But if you use 8 bit per character, you would only need a 160/8 = 20 character l...
How to get a list of installed android applications and pick one to run
...sked a similar question to this earlier this week but I'm still not understanding how to get a list of all installed applications and then pick one to run.
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How to detect when WIFI Connection has been established in Android?
...that a valid network connection for HTTP exists. What should I listen for and what additional tests do I need to make to know that a valid connection exists.
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String Concatenation using '+' operator
Looking at the string class metadata, I only see the operators == and != overloaded. So how is it able to perform concatenation for the ' + ' operator?
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in iPhone App How to detect the screen resolution of the device
...ays this will return a 1.0f, while Retina Display devices will give a 2.0f and the iPhone 6 Plus (Retina HD) will give a 3.0f.
Now if you want to get the pixel width & height of the iOS device screen you just need to do one simple thing.
CGSize screenSize = CGSizeMake(screenBounds.size.width *...
Automatically add newline at end of curl response body
...ly annoying condition where the shell prompt is in the middle of the line, and escaping is messed up enough that when I put the last curl command on the screen, deleting characters from that curl command deletes the wrong characters.
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Add comma to numbers every three digits
... Works perfectly! Thanks to Paul Creasey for simply, elegant code and thanks to Doug Neiner for putting it in plugin format. Credit given to both.
– Steve
Jan 2 '10 at 4:31
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