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What are the use cases for selecting CHAR over VARCHAR in SQL?
...the word "FooBar"
CHAR(6) = 6 bytes (no overhead)
VARCHAR(100) = 8 bytes (2 bytes of overhead)
CHAR(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Note: Microsoft SQL...
Converting array to list in Java
...ith the Arrays.asList utility method.
Integer[] spam = new Integer[] { 1, 2, 3 };
List<Integer> list = Arrays.asList(spam);
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What is a good Java library to zip/unzip files? [closed]
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I know its late and there are lots of answers but this zip4j is one of the best libraries for ...
How do I compile and run a program in Java on my Mac?
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edited Mar 2 '10 at 5:44
answered Mar 2 '10 at 5:30
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Is “else if” a single keyword?
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They are not a single keyword if we go to the draft C++ standard section 2.12 Keywords table 4 lists both if and else separately and there is no else if keyword. We can find a more accessible list of C++ keywords by going to cppreferences section on keywords.
The grammar in section 6.4 also make...
Passing an Array as Arguments, not an Array, in PHP
...for a function, dereferencing the array into the standard func($arg1, $arg2) manner. But now I'm lost on how to do it. I recall the manner of passing by reference, how to "glob" incoming parameters ... but not how to de-list the array into a list of arguments.
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Is it safe to shallow clone with --depth 1, create commits, and pull updates again?
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Postgres: INSERT if does not exist already
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Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON C...