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35 lines
992 B
Markdown
35 lines
992 B
Markdown
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---
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en_copy: true
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---
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# Comparison functions {#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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## equals, a = b and a == b operator {#function-equals}
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## notEquals, a ! operator= b and a <> b {#function-notequals}
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## less, < operator {#function-less}
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## greater, > operator {#function-greater}
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## lessOrEquals, <= operator {#function-lessorequals}
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## greaterOrEquals, >= operator {#function-greaterorequals}
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[Original article](https://clickhouse.tech/docs/en/query_language/functions/comparison_functions/) <!--hide-->
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