欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  数据库

MySQl在开发和生产不同环境下的索引对比

程序员文章站 2022-05-19 16:00:02
...
--1.创建索引信息表
create table `t_index_update` (
`table_name` varchar(20) COLLATE gbk_bin DEFAULT NULL,
`index_name` varchar(20) COLLATE gbk_bin DEFAULT NULL,
`index_cols` varchar(100) COLLATE gbk_bin DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=gbk COLLATE=gbk_bin;
--2.插入线下索引信息表
insert into t_index_update()
select
table_name,
index_name,
group_concat(distinct concat('`', column_name, '`') order by seq_in_index asc separator ', ') as index_cols
from information_schema.STATISTICS
where table_schema= 'elk'
and column_name<>'seq_id'
and index_name<>'primary'
group by table_name, index_name
order by table_name asc, index_name asc;
--3.同步线下索引信息表到线上
--4.构建删除和修改过的索引的删除语句
select concat('alter table `',a.table_name,'` drop index ',a.index_name,';')
from
(
select
table_name,
index_name,
group_concat(distinct concat('`', column_name, '`') order by seq_in_index asc separator ', ') as index_cols
from information_schema.STATISTICS
where table_schema= 'elk'
and column_name<>'seq_id'
and index_name<>'primary'
group by table_name, index_name
) a
left join t_index_update b on b.table_name and b.index_name=a.index_name and b.index_cols=a.index_cols
where b.index_name is null;
--5.构建新加索引的的新加语句
select concat('alter table `',a.table_name,'` add index ',a.index_name,'(',a.index_cols,');')
from t_index_update a
left join (
select
table_name,
index_name,
group_concat(distinct concat('`', column_name, '`') order by seq_in_index asc separator ', ') as index_cols
from information_schema.STATISTICS
where table_schema= 'elk'
and column_name<>'seq_id'
and index_name<>'primary'
group by table_name, index_name
) b on b.table_name and b.index_name=a.index_name and b.index_cols=a.index_cols
where b.index_name is null;

以上就是MySQl在开发和生产不同环境下的索引对比的详细内容,更多请关注其它相关文章!