PHP test null.php

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Hostnamefreddy
uname -aLinux freddy 4.4.0-22-generic #40-Ubuntu SMP Thu May 12 22:03:46 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
date2016-05-31

SELECT top 1 * FROM #MyTable WHERE n = 1 -- '' -> (Empty String)
SELECT top 1 * FROM #MyTable WHERE n = 2 -- NULL -> (NULL)
SELECT top 1 * FROM #MyTable WHERE n = 3 -- ' ' -> ' '
SELECT top 1 * FROM #MyTable WHERE n = 4 -- 'a' -> 'a'

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