| [`COUNT(DISTINCT)`](https://dev.mysql.com/doc/refman/5.7/en/aggregate-functions.html#function_count-distinct) | 返回不同值的数目 | | [`SUM()`](https://dev ...
Learn about the supported aggregate functions in TiDB. /docs/dev/functions-and-operators/aggregate-group-by-functions/ /docs/dev/reference/sql/functions-and-operators ...