http://www.2cto.com/database/201503/380348.html
https://wenku.baidu.com/view/629d6cf4ddccda38366baf57.html
MySQL的表分区详解 - 查看分区数据量,查看全库数据量
SELECT
partition_name part,
partition_expression expr,
partition_description descr,
table_rows
FROM
INFORMATION_SCHEMA.partitions
WHERE
TABLE_SCHEMA = schema()
AND TABLE_NAME='table';