mysql基本功能+show+innodb+索引+慢sql+explain

基本功能

DML
DDL
DCL

show语句

show engines
show databases;
show tables;
show status
show processlist

慢sql

索引

创建索引，删除索引的语法
alter table table_name add index index_name (column_list) ;
alter table table_name add unique (column_list) ;
alter table table_name add primary key (column_list) ;
create index index_name on table_name (column_list) ;
create unique index index_name on table_name (column_list) ;

explain说明