mysql 查看单个表每个索引的大小

/*单个表每个索引的大小*/

SELECT
       sum(stat_value) pages,
       table_name part,
       index_name,
       concat(round(sum(stat_value)/1000000,2),'M',' rows') * @@innodb_page_size size
FROM
       mysql.innodb_index_stats
WHERE
           table_name = '你的表名'
       AND database_name = '你的数据库名'
       AND stat_description LIKE 'Number of pages in the index'
GROUP BY
       table_name, index_name;

错误说明：用户名权限不够