A collection of common MySQL commands

First, connect MySQL

Format: mysql-h host address-u user name-P user Password

1, Example 1: Connect to MySQL on this machine.

First in the Open DOS window, and then into the directory Mysqlbin, and then type the command mysql-uroot-p, enter after the prompt you to lose the password, if just installed MySQL, superuser root is no password, so direct return can enter into MySQL, The MySQL prompt is:mysql>.

2, Example 2: Connect to the remote host MySQL. Assume the IP of the remote host is: 110.110.110.110, username is root, password is abcd123. Type the following command:

Mysql-h110.110.110.110-uroot-pabcd123

(Note: U and root can be without spaces, others are the same)

3, exit MySQL command: Exit (enter).

Second, modify the password

Format: Mysqladmin-u username-P Old password password new password

1, Example 1: To root add a password ab12. First enter the directory Mysqlbin in DOS, and then type the following command:

Mysqladmin-uroot-password AB12

Note: Since Root does not have a password at the beginning, the-p old password can be omitted.

2, Example 2: Then the root password changed to djg345.

MYSQLADMIN-UROOT-PAB12 Password djg345

Third, add new users. (Note: Unlike the above, the following are the commands in the MySQL environment, followed by a semicolon as the command Terminator)

Format: Grant Select on database. * To User name @ login host identified by "password"

Example 1, add a user test1 password for ABC, so that he can log on any host, and all databases have query, insert, modify, delete permissions. First connect the root user to MySQL, and then type the following command:

Grant Select,insert,update,

Delete on *.* to test1@ "%" identified by "ABC";

But for example 1 the increased user is very dangerous and you want someone who knows Test1 's password so that he can log on to your MySQL database on any computer on the Internet and can do whatever it wants with your data, as shown in Example 2.

Example 2, add a user test2 password for ABC, so that he can only log on the localhost, and can query the database mydb, insert, modify, delete operations (localhost refers to the local host, that is, the MySQL database of the host), This allows a user to use a password that knows test2, and he cannot access the database directly from the Internet, only through a Web page on the MySQL host.

Grant Select,insert,update,

Delete on mydb.* to test2@localhost identified by "ABC";

If you do not want to test2 the password, you can make another command to eliminate the password.

Grant Select,insert,update,delete on MyDB

. * To Test2@localhost identified by "";

The above mentioned issues such as login, increase user, password change, and so on. Let's look at MySQL about database operations. Note: You must first log in to MySQL, and the following actions are performed under the MySQL prompt, and each command ends with a semicolon.

First, the Operation skill

1, if you hit the command, when you find that you forgot to add a semicolon, you do not need to repeat the command, as long as a semicolon to enter on it. That is, you can divide a complete command into several lines and then complete it with a semicolon as the closing sign.

2, you can use the cursor up and down keys to pull up the previous command. But I used to use a MySQL older version does not support. I'm using a mysql-3.23.27-beta-win.

Second, display command

1. Display Database list:

show databases;

Only two databases were initially: MySQL and test. MySQL Library is very important it has MySQL system information, we change the password and new users, is actually using this library to operate.

2, display the data table in the library:

Use MySQL; Open the library, learned foxbase must be not unfamiliar with it

Show tables;

3, display the structure of the data table:

describe table name;

4, build the library:

Create database library name;

5, the establishment of the table:

Use library name;

CREATE TABLE table name (field set list);

6, delete the database and delete the table:

drop Database library name;

The drop table table name;

7. Empty the record of the table:

Delete from table name;

8, display the records in the table:

SELECT * from table name;

Example of 三、一个 and table-building and inserting data

Drop database if exists school; Delete if there is school

Create Database School; Build a library School

Use school; Open Library School

CREATE TABLE teacher//Create tables Teacher

(

ID int (3) auto_increment NOT null primary key,

Name Char (a) NOT NULL,

Address varchar default ' Shenzhen ',

Year Date

); Build Table End

The following is a total of 2 pages for the Insert field.

Insert into teacher values (', ' Glchengang ', ' Shenzhen One ', ' 1976-10-10 ');

Insert into teacher values (', ' Jack ', ' Shenzhen One ', ' 1975-12-23 ');

Note: In the table (1), set the ID to a number field of length 3: Int (3) and let it automatically add one for each record: Auto_increment cannot be empty: NOT null and let him be the primary field primary key (2) sets name to a character field of length 10 (3 Sets the address to a character field of length 50, and the default value is Shenzhen. What is the difference between varchar and char, only to wait for later articles to say. (4) Set year as Date field.

If you type the above command at the MySQL prompt, it's not easy to debug. You can write the above command in a text file as if it were school.sql, then copy to C: and enter the directory Mysqlbin in DOS, and then type the following command:

Mysql-uroot-p Password < C:school.sql

If successful, there is no display on a single line, and if there is an error, there is a hint. (The above command has been debugged and you can use it only if you remove the comment.)

Iv. transferring text data to a database

1, the text data should conform to the format: The field data is separated by the TAB key, null value with N to replace.

Cases:

3 Rose Shenzhen II 1976-10-10

4 Mike Shenzhen one 1975-12-23

2. Data incoming command load infile "filename" into table name.

Note: You'd better copy the files to the Mysqlbin directory and use the using command to hit the library where the table resides.

V. BACKUP DATABASE:

1, mysqldump--opt school>school.bbb

Mysqldump--opt SCHOOL>SCHOOL.BBB

(Command executes in DOS Mysqlbin directory)

Note: Back up the database school to the school.bbb file, school.bbb is a text file, file name, open to see if you will find something new.

PostScript: In fact, MySQL's operations on the database and other SQL class database is similar, you'd better find the book to read the SQL. I only introduce some basic, in fact, I only understand these, hehe. The best MySQL tutorial or "Yan Zi" translation of the "MySQL Chinese reference manual" not only free of all relevant sites have downloads, and it is the most authoritative. Unfortunately, it is not a CHM format like "PHP4 Chinese Manual", which is not convenient when looking for function commands.

2, modify the login password

1) mysqladmin-u user name-p old password password new password:

Example: mysqladmin-u root password 21century

Note: Since Root does not have a password at the beginning, the-p old password can be omitted.

2) directly modify the user table root password:

mysql> user MySQL;

mysql> Update user Set Pasword=password (' 21century ') where user= ' root ';

mysql> flush Privileges;

Note: Flush privileges means that the memory authorization table is forced to flush, otherwise the password in the buffer is used.

3, test password is modified successfully:

1 Login without password:

[Root@test1 local]# MySQL

ERROR 1045:access denied for user: ' Root@localhost ' (Using password:no)

An error is displayed, indicating that the password has been modified.

2 Login with modified password:

[Root@test1 local]# mysql-u root-p

Enter Password: (Enter the modified password 21century)

Welcome to the MySQL Monitor. Commands End With; or G.

Your MySQL Connection ID is 177 to server version:3.23.48

Type ' help, ' or ' h ' for help. Type ' C ' to clear the buffer.

Mysql>

Success!

This is through the mysqladmin command to modify the password, or you can change the password by modifying the library.

4. Start and stop:

Start: MySQL changed from version 3.23.15, the default installation service to use the MySQL user to start, do not allow the root user to start.

If you want to start with the root user, you must add the--user=root parameter (./safe_mysqld--user=root &) Stop: mysqladmin-u root-p shutdown.

5. Export meeting Database:

Mysqldump-uroot-p21century Meeting > Db_meeting.sql

Guide Person dbname Database:

Mysqldump-uroot-p21century dbname < Xxx.sql

The import database can also execute a large number of SQL statements at a time, similar to the @my_script.sql in Oracle, which is useful when using mysqldump does not work.

Example: #./mysql-uroot-p

(Note: Create DATABASE, use DatabaseName, CREATE TABLE, and insert INTO statements can be written in the footsteps file above)

6, to the table renamed:

RENAME TABLE ztemp to Ztemp4;

7, modify the field properties:

ALTER TABLE bbabase change news_id ID VARCHAR (5) is not NULL;

8, add a field after the content in the table:

ALTER TABLE bbabase ADD leave_time DATETIME not NULL after.