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When to use Common Table Expression (CTE)
I have begun reading about Common Table Expression and cannot think of a use case where I would need to use them. They would seem to be redundant as the same can be done with derived tables. Is there something I am missing or not understanding well? Can someone give me a simple example of limitati...
Saving changes after table edit in SQL Server Management Studio
If I want to save any changes in a table, previously saved in SQL Server Management Studio (no data in table present) I get an error message:
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How to define hash tables in Bash?
What is the equivalent of Python dictionaries but in Bash (should work across OS X and Linux).
15 Answers
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How do I write the 'cd' command in a makefile?
For example, I have something like this in my makefile:
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6
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Why use symbols as hash keys in Ruby?
A lot of times people use symbols as keys in a Ruby hash.
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What is the difference between encode/decode?
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The decode method of unicode strings really doesn't have any applications at all (unless you have some non-text data in a unicode string for some reason -- see below). It is mainly there for historical reasons, i think. In Python 3 it is completely gone.
u...
How do I speed up the gwt compiler?
We're starting to make heavier use of GWT in our projects, and the performance of the GWT compiler is becoming increasingly annoying.
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What is the difference between a heuristic and an algorithm?
...n automated solution to a problem. What the algorithm does is precisely defined. The solution could or could not be the best possible one but you know from the start what kind of result you will get. You implement the algorithm using some programming language to get (a part of) a program.
Now, some...
In PHP, what is a closure and why does it use the “use” identifier?
I'm checking out some PHP 5.3.0 features and ran across some code on the site that looks quite funny:
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Turn a string into a valid filename?
I have a string that I want to use as a filename, so I want to remove all characters that wouldn't be allowed in filenames, using Python.
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