mysql常用操作

create database new_dbname;--新建数据库
drop database old_dbnane; --删除数据库
show databases;--显示数据库
use databasename;--使用数据库
select database();--查看已选择的数据库

show tables;--显示当前库的所有表
create table tablename(fieldname1 fieldtype1,fieldname2 fieldtype2,..)[ENGINE=engine_name];--创建表
drop table tablename; --删除表
create table tablename select statement;--通过子查询创建表
desc tablename;--查看表结构
show create table tablename;--查看建表语句

alter table tablename add new_fielname new_fieldtype;--新增列
alter table tablename add new_fielname new_fieldtype after 列名1;--在列名1后新增列
alter table tablename modify fieldname new_fieldtype;--修改列
alter table tablename drop fieldname;--删除列
alter table tablename_old rename tablename_new;--表重命名

insert into tablename(fieldname1,fieldname2,fieldnamen) valuse(value1,value2,valuen);--增
delete from tablename [where fieldname=value];--删
update tablename set fieldname1=new_value where filename2=value;--改
select * from tablename [where filename=value];--查

truncate table tablename;--清空表中所有数据,DDL语句

show engines;--查看mysql现在已提供的存储引擎:
show variables like '%storage_engine%';--查看mysql当前默认的存储引擎
show create table tablename;--查看某张表用的存储引擎(结果的"ENGINE="部分)
alter table tablename ENGINE=InnoDB--修改引擎
create table tablename(fieldname1 fieldtype1,fieldname2 fieldtype2,..) ENGINE=engine_name;--创建表时设置存储引擎
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作者:上杉绘梨衣-
来源:CSDN
原文:https://blog.csdn.net/wjlwangluo/article/details/78165588
版权声明:本文为博主原创文章,转载请附上博文链接!

版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/royjj/article/details/49822373
mysql> CREATE TABLE `employees1` (
    ->   `id` int(11) NOT NULL,
    ->   `fname` varchar(30) DEFAULT NULL,
    ->   `lname` varchar(30) DEFAULT NULL,
    ->   `hired` date NOT NULL DEFAULT '1970-01-01',
    ->   `separated` date NOT NULL DEFAULT '9999-12-31',
    ->   `job_code` int(11) NOT NULL,
    ->   `store_id` int(11) DEFAULT NULL
    -> ) ENGINE=InnoDB DEFAULT CHARSET=latin1
    -> /*!50100 PARTITION BY RANGE (store_id)
    -> (PARTITION p0 VALUES LESS THAN (6) ENGINE = InnoDB,
    ->  PARTITION p1 VALUES LESS THAN (11) ENGINE = InnoDB,
    ->  PARTITION p2 VALUES LESS THAN (16) ENGINE = InnoDB,
    ->  PARTITION p3 VALUES LESS THAN (21) ENGINE = InnoDB) */;
Query OK, 0 rows affected (0.59 sec)


mysql> show create table employees1;
+------------
| Table      | Create Table                                                                                           
------------------------------------------------------------------------------------------------------------------+
| employees1 | CREATE TABLE `employees1` (
  `id` int(11) NOT NULL,
  `fname` varchar(30) DEFAULT NULL,
  `lname` varchar(30) DEFAULT NULL,
  `hired` date NOT NULL DEFAULT '1970-01-01',
  `separated` date NOT NULL DEFAULT '9999-12-31',
  `job_code` int(11) NOT NULL,
  `store_id` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY RANGE (store_id)
(PARTITION p0 VALUES LESS THAN (6) ENGINE = InnoDB,
 PARTITION p1 VALUES LESS THAN (11) ENGINE = InnoDB,
 PARTITION p2 VALUES LESS THAN (16) ENGINE = InnoDB,
 PARTITION p3 VALUES LESS THAN (21) ENGINE = InnoDB) */ |
+------------
1 row in set (0.11 sec)


mysql> alter table employees1 drop partition p0,p3;     
Query OK, 0 rows affected (0.14 sec)
Records: 0  Duplicates: 0  Warnings: 0


mysql>  show create table employees1;
+--------------------------------------------------------------------------------------------+
| Table      | Create Table                                                                                                  
------------------------------------------------------------------------------------------+
| employees1 | CREATE TABLE `employees1` (
  `id` int(11) NOT NULL,
  `fname` varchar(30) DEFAULT NULL,
  `lname` varchar(30) DEFAULT NULL,
  `hired` date NOT NULL DEFAULT '1970-01-01',
  `separated` date NOT NULL DEFAULT '9999-12-31',
  `job_code` int(11) NOT NULL,
  `store_id` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY RANGE (store_id)
(PARTITION p1 VALUES LESS THAN (11) ENGINE = InnoDB,
 PARTITION p2 VALUES LESS THAN (16) ENGINE = InnoDB) */ |
+-----------------------------------+

1 row in set (0.02 sec)
---------------------
作者:lixora
来源:CSDN
原文:https://blog.csdn.net/lixora/article/details/49822373
版权声明:本文为博主原创文章,转载请附上博文链接!

原文地址:https://www.cnblogs.com/shenggong/p/10697073.html