mysql操作基本命令

查看索引 ： show index from table_name

创建索引：create index index_name on table_name(column_name)
创建唯一索引：create unique index index_name on table_name(column_name)
创建联合索引：create index index_name on table_name(column1_name,column2_name)

 

删除索引：drop index index_name on table_name

查看创建表语句：show create table table_name

新建表：create table table_name(

              id int not null auto_increment,
              name varchar(50) not null,
              age int not null,
              primary key(id)

      ); 

插入语句：insert into table_name(column1_name, column2_name) values (column1_value,column2_value)

清空表中信息：truncate table table_name

 

查看所有列：show full columns from table_name

 

左连接：
      select a.name, b.name from A a left join B b on a.id = b.id;    (以表A为标准)
右连接：
　　　 select a.name, b.name from A a right join B b on a.id = b.id;   (以表B为标准)

内连接：
      select a.name, b.name from A a inner join B b on a.id = b.id;
        等价于
      select a.name, b.name from A a, B b where a.id = b.id;

 

#!/bin/bash
i=1;
MAX_INSERT_ROW_COUNT=$1;
while [ $i -le $MAX_INSERT_ROW_COUNT ]
do
  mysql -uroot -proot dbname -e "insert into tablename (name,age,createTime) values ('HELLO$i',$i % 99,NOW());"
  d=$(date +%M-%d\ %H\:%m\:%S)
  echo "INSERT HELLO $i @@ $d" 
  i=$(($i+1))
  sleep 0.05
done
 
exit 0