Linux under MySQL Insert update delete transaction user management

Linux under MySQL Insert update delete transaction user management

1.INSERT INSERT statement Format:

INSERT into Tb_name (Field 1, Field 2, ...) Values (value 1, value 2, ...) [, (value 1, value 2, ...),...];

INSERT into table name SET field 1= value 1, field 2= value 2,...;

INSERT into table name (Field 1, Field 2,...) SELECT (field 1, Field 2,...) From table name [WHERE condition];

2.REPLACE INSERT statement Format:

REPLACE into Tb_name (Field 1, Field 2, ...) Values (value 1, value 2, ...) [, (value 1, value 2, ...),...];

REPLACE into table name SET field 1= value 1, field 2= value 2,...;

REPLACE into table name (Field 1, Field 2,...) SELECT (field 1, Field 2,...) From table name [WHERE condition];

3.DELETE Delete the contents of the table:

Delect from table name WHERE condition;

Delect from table name; #清空表但不会重置计数器

TRUNCATE table name; #清空表并重置AUTOCREMENT计数器

4.UPDATE Update the contents of the table

UPDATE table name SET field 1= ..., field 2= ... WHERE condition;

5. Lock table:

Read Lock: Shared lock

Write Lock: Exclusive lock

LOCK TABLES table name {read| WRITE};

UNLOCK TABLES

6. Business

6.1. Explicitly start the transaction:

Start TRANSACTION: Start transaction

ROLLBACK: Rolling back

Commit: Submit #注意提交后就不能回滚

6.2. No explicitly initiated transaction:

Autocommit: Can achieve automatic submission, each operation is submitted directly;

Recommendation: Explicitly use transactions, and turn off autocommit;

SET autocommit=0;

SET @ @autocommit;

6.3. Transaction Save Point

Save point: SavePoint name

Rollback to save point: ROLLBACK to name

7. Isolation Level:

Read-uncommitted: Read not submitted

Read-committed: Read Commit

Repeatable-read: Can be stressed

SERIALIZABLE: Serializable

SELECT @ @tx_isolation;

SET tx-isolation= ' read-uncommited ';

8. Create a user

CREATE USER [email protected] '% ' identified by ' Redhat ';

5. Authorized User Rights

GRANT CREATE on ' Willow '. * to ' willow ' @ '% '

GRANT INSERT on ' Willow '. * to ' willow ' @ '% '

GRANT ALTER on ' Willow '. * to ' willow ' @ '% '

GRANT SELECT on ' Willow '. * to ' willow ' @ '% '

GRANT UPDATE (age) on willow.students to [email protected] '% '; #授权用户仅字段修改权限

6. Delete a user

DROP user ' username ' @ ' host '

9. Renaming users

RENAME user old username to new user name

10. Retrieving user authorizations

REVOKE SELECT on willow.* from [email protected] '% ';

11.mysql admin password forgot to retrieve password:

Stop MySQL Service

Service Mysqld Stop

Vim/etc/init.d/mysqld

Inserting in the start statement

--skip-grant-tables

--skip-networking

650) this.width=650; "Src=" Http://s5.51cto.com/wyfs02/M00/83/CE/wKioL1d8y0qTaY-vAAHk9mVTHrc535.jpg-wh_500x0-wm_3 -wmp_4-s_1694436580.jpg "title=" 1.jpg "alt=" Wkiol1d8y0qtay-vaahk9mvthrc535.jpg-wh_50 "/>

Service Mysqld Stop

MySQL #本地连上服务器此时跳过授权直接登入

Use MySQL;

UPDATE user SET Password=password (' Redhat ') WHERE user= ' root ';

Note: You cannot modify the password directly with the SET command because the authorization has been skipped.

# set PASSWORD for ' root ' @ ' localhost ' =password (' Redhat ');

Modify its password directly by updating the authorization table, and remove the mysqld that you just added and restart the server MySQL.

Two parameters are passed when starting Mysqld_safe:

--skip-grant-tables

--skip-networking

--skip-name-resolve

This article is from the "Xavier Willow" blog, please be sure to keep this source http://willow.blog.51cto.com/6574604/1811720

Linux under MySQL Insert update delete transaction user management