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SQL Add foreign key to existing column
...sed an error trying to create the relationships to the other table. Thanks all.
– ExceptionLimeCat
Apr 30 '12 at 20:35
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What exactly does big Ө notation represent?
I'm really confused about the differences between big O, big Omega, and big Theta notation.
6 Answers
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Drop all tables whose names begin with a certain string
How can I drop all tables whose names begin with a given string?
14 Answers
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Catch All Bugs with BugTrap! - 开源 & Github - 清泛网移动版 - 专注C/C++及内核技术
Catch All Bugs with BugTrap!Catch-All-Bugs-with-BugTrapA tool that can catch unhandled errors and exceptions, and deliver error reports to remote support serversDownload...A tool that can catch unhandled errors and exceptions, and deliver error reports to remote support servers
Download documen...
How to apply multiple styles in WPF
...r, check out the following xaml below to get around that restriction. Basically, it means you need to give the Style a key and reference it with that key.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Pa...
PHP script to loop through all of the files in a directory?
I'm looking for a PHP script that loops through all of the files in a directory so I can do things with the filename, such as format, print or add it to a link. I'd like to be able to sort the files by name, type or by date created/added/modified. (Think fancy directory "index".) I'd also like to be...
Variable interpolation in the shell
I have a variable called filepath=/tmp/name .
3 Answers
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“for” vs “each” in Ruby
...The reason why x remains in the for scenario is due to the fact that (generally speaking) keywords don't create new scopes. if, unless, begin, for, while, etc. all work with the current scope. #each however accepts a block. Blocks always add their own scope on top of the current scope. Meaning that ...
mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
Applicatives compose, monads don't
...t a value in s can determine the behaviour of a computation in m t. Monads allow interference between the value and computation layers. The (<*>) operator allows no such interference: the function and argument computations don't depend on values. This really bites. Compare
miffy :: Monad m =&...