在標準MySQL 5.6上查詢沒有使用過的索引的SQL

select distinct
    mysql.innodb_index_stats.table_name,
    mysql.innodb_index_stats.index_name
from
    mysql.innodb_index_stats
where
    concat(mysql.innodb_index_stats.index_name,
            mysql.innodb_index_stats.table_name) not in (select 
            concat(information_schema.statistics.index_name,
                        information_schema.statistics.table_name)
        from
            information_schema.statistics)
        and mysql.innodb_index_stats.index_name <> 'GEN_CLUST_INDEX';