查看超过3个月未收集统计的表

select * from mysql.innodb_table_stats where last_update < DATE_SUB(current_timestamp(), INTERVAL 90 DAY) and database_name not in ('sys','information_schema','mysql','performance_schema');

建议你跑下巡检, 还有冷表, 没得主键的表, 冗余索引等
巡检工具参考: https://github.com/ddcw/inspection