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Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...
What is __main__.py?
What is the __main__.py file for, what sort of code should I put into it, and when should I have one?
5 Answers
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How to sum up elements of a C++ vector?
What are the good ways of finding the sum of all the elements in a std::vector ?
11 Answers
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Python try-else
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The statements in the else block are executed if execution falls off the bottom of the try - if there was no exception. Honestly, I've never found a need.
However, Handling Exceptions notes:
The use of the else clause is better
than adding additional code to the try
clause be...
Recommended way to get hostname in Java
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Strictly speaking - you have no choice but calling either hostname(1) or - on Unix gethostname(2). This is the name of your computer. Any attempt to determine the hostname by an IP address like this
InetAddress.getLocalHost().getHostName()
is bound to fail in some cir...
How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar
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I actually just implemented this on one of my projects (your question and the other wrong answer hinted at what to do). I tried Sergio's answer but had exception issues when actually running on a device.
Yes you create two fetch ...
Download the Android SDK components for offline install
Is it possible to download the Android SDK components for offline install without using the SDK Manager?
The problem is I am behind a firewall which I have no control over and both sites download URLs seem to be blocked (throws a connection refused exception)
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When to use NSInteger vs. int
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You usually want to use NSInteger when you don't know what kind of processor architecture your code might run on, so you may for some reason want the largest possible integer type, which on 32 bit systems is just an int, while on a ...
Python JSON serialize a Decimal object
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The problem was that DecimalEncoder()._iterencode(decimal.Decimal('3.9')).next() returned the correct '3.9', but DecimalEncoder()._iterencode(3.9).next() returned a generator object which would only return '3.899...' when you piled on another .next(). Generator f...
Entity Framework 4 Single() vs First() vs FirstOrDefault()
...where you are expecting a single record but they won't warn you if you actually get more than that single record back which could be important depending on the situation.
– Steve Willcock
Aug 14 '10 at 22:47
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