ClickHouse/docs/en/sql_reference/functions/comparison_functions.md

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36	Comparison

Comparison functions

Comparison functions always return 0 or 1 (Uint8).

The following types can be compared:

• numbers
• strings and fixed strings
• dates
• dates with times

within each group, but not between different groups.

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.

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.

equals, a = b and a == b operator

notEquals, a ! operator= b and a <> b

less, < operator

greater, > operator

lessOrEquals, <= operator

greaterOrEquals, >= operator

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