Mysql索引优化

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select * from payment where staff_id = 2 and customer_id = 584;

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Mysql> select count(distinct customer_id),count(distinct staff_id) from payment;+-----------------------------+--------------------------+| count(distinct customer_id) | count(distinct staff_id) |+-----------------------------+--------------------------+|                         599 |                        2 |+-----------------------------+--------------------------+

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大专栏  Mysql索引优化lass="line">create table test(id int not null primary key,//主键name varchar(10) not null,unique(id)//唯一索引)engine = innodb;

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create table test(id int not null primary key,//主键name varchar(10) not null,key(name,id)//索引)engine = innodb;

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use information_schema;select a.table_schema as '数据名',a.table_name as '表名',a.index_name as '索引1',b.index_name as '索引2',a.column_name as '重复列名' from statistics a join statistics b on a.table_schema = b.table_schema and a.table_name = b.table_name and a.seq_in_index = b.seq_in_index and a.column_name = b.column_name where a.seq_in_index = 1 and a.index_name <> b.index_name;

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pt-duplicate-key-checker -uxxx -pxxx -hxxx

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pt-index-usage -uxxx -pxxx /xxx/Mysql-slow.log