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32 lines
982 B
Markdown
32 lines
982 B
Markdown
# Comparison functions
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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: Up until version 1.1.54134, signed and unsigned numbers were compared the same way as in C++. In other words, you could get an incorrect result in cases like SELECT 9223372036854775807 > -1. This behavior changed in version 1.1.54134 and is now mathematically correct.
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## equals, a = b and a == b operator
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## notEquals, a ! operator= b and a `<>` b
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## less, `< operator`
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## greater, `> operator`
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## lessOrEquals, `<= operator`
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## greaterOrEquals, `>= operator`
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