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ORA-00979 not a group by expression
...ults to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like this:
FOO BAR
0 A
0 B
and you run SELECT * FROM table GROUP BY foo. This means the database must return a single row as result with the first column 0 to fulfill t...
What is the relative performance difference of if/else versus switch statement in Java?
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That's micro optimization and premature optimization, which are evil. Rather worry about readabililty and maintainability of the code in question. If there are more than two if/else blocks glued together or its size is unpredictable, then you may high...
Python list subtraction operation
...set(x) - set(y))
>>> z
[0, 8, 2, 4, 6]
Or you might just have x and y be sets so you don't have to do any conversions.
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How to redirect output of an entire shell script within the script itself?
...ll of the output of a Bourne shell script to somewhere, but with shell commands inside the script itself?
5 Answers
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Vim: Move cursor to its last position
...r to its previous position (while in normal mode)? Something to cycle back and forth in the list of previous cursor positions would be ideal. But also just to switch to the last location would suffice (something like cd - in bash with directories).
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How to input a regex in string.replace?
...racters" which need to be escaped (i.e. with a backslash placed in front - and the rules are different inside and outside character classes.) There is an excellent online tutorial at: www.regular-expressions.info. The time you spend there will pay for itself many times over. Happy regexing!
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How do I get the calling method name and type using reflection? [duplicate]
I'd like to write a method which obtains the name of the calling method, and the name of the class containing the calling method.
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OS X Framework Library not loaded: 'Image not found'
...ght now I just have a test framework created: TestMacFramework.framework and I'm trying to import it into a brand new OS X Application project.
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Google Guava vs. Apache Commons [closed]
I was looking for a bidirectional map implementation in Java, and stumbled upon these two libraries:
5 Answers
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Junit: splitting integration test and Unit tests
...hese tests (apart from most not working) are a mixture of actual unit test and integration tests (requiring external systems, db etc).
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