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37 lines
1.1 KiB
ReStructuredText
37 lines
1.1 KiB
ReStructuredText
Comparison functions
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--------------------
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Comparison functions always return 0 or 1 (Uint8).
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The following types can be compared:
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* numbers
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* strings and fixed strings
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* dates
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* dates with times
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within each group, but not between different groups.
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For example, you can't compare a date with a string. You have to use a function to convert the string to a date, or vice versa.
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Strings are compared by bytes. A shorter string is smaller than all strings that start with it and that contain at least one more character.
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Note: before version 1.1.54134 signed and unsigned numbers were compared the same way as in C++. That is, you could got an incorrect result in such cases: SELECT 9223372036854775807 > -1. From version 1.1.54134, the behavior has changed and numbers are compared mathematically correct.
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equals, a = b and a == b operator
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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notEquals, a != b and a <> b operator
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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less, < operator
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~~~~~~~~~~~~~~~~
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greater, > operator
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~~~~~~~~~~~~~~~~~~~
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lessOrEquals, <= operator
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~~~~~~~~~~~~~~~~~~~~~~~~~
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greaterOrEquals, >= operator
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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