Here I am trying to give a full instant guide to Mysql commands that will help people for their easy usage.
To login (from unix shell) use -h only if needed.
[mysql dir]/bin/mysql -h hostname -u username -p password
To login (from windows)
[mysql dir]/bin/mysql.exe -h hostname -u username -p password
Create a database.
mysql> create database [databasename];
List all databases on the server.
mysql> show databases;
Switch to a database.
mysql> use [db name];
To see all the tables in the db.
mysql> show tables;
To see table’s field formats.
mysql> describe [table name];
To delete a db.
mysql> drop database [database name];
To delete a table.
mysql> drop table [table name];
Show all data from a table.
mysql> SELECT \* FROM [table name];
To return columns and column information.
mysql> show columns from [table name];
Show particular rows with the given value.
mysql> SELECT \* FROM [table name] WHERE [field name] = "value";
Show all records containing the name “Something” AND the phone number ‘0123456789’.
mysql> SELECT \* FROM [table name] WHERE name = "Something" AND phone_number = '0123456789';
Show all records not containing the name “Something” AND the phone number ‘0123456789’ order by the phone_number field.
mysql> SELECT \* FROM [table name] WHERE name != "Something" AND phone_number = '0123456789' order by phone_number;
Show all records starting with the letters ‘Something’ AND the phone number ‘0123456789’.
mysql> SELECT \* FROM [table name] WHERE name like "****Something%" AND phone_number = '0123456789';
Show all records starting with letters ‘Something’ AND the phone number ‘0123456789’ limit to records 1 through 5.
mysql> SELECT \* FROM [table name] WHERE name like "****Something%" AND phone_number = '0123456789' limit 1,5;
Use a regular expression to find records. Use “REGEXP BINARY” to force case-sensitivity. This finds any record beginning with a.
mysql> SELECT \* FROM [table name] WHERE rec RLIKE "^a";
Show unique records.
mysql> SELECT DISTINCT [column name] FROM [table name];
Show selected records sorted in an ascending (asc) or descending (desc).
mysql> SELECT [col1],[col2] FROM [table name] ORDER BY [col2] DESC;
Return number of rows.
mysql> SELECT COUNT(\*) FROM [table name];
Sum column.
mysql> SELECT SUM(\*) FROM [table name];
Creating a new user. Login as root. Switch to the MySQL db. Make the user. Update privs.
# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO user (Host,User,Password) VALUES('%','username',PASSWORD('password'));
mysql> flush privileges;**
Change a users password from unix shell.
# [mysql dir]/bin/mysqladmin -u username -h hostname -ppassword 'new-password'
Change a users password from MySQL prompt. Login as root. Set the password. Update privileges.
mysql -u root -p
mysql> SET PASSWORD FOR 'user'@'hostname' = PASSWORD('password');
mysql> flush privileges;
Recover a MySQL root passwbord. Stop the MySQL server process. Start again with no grant tables. Login to MySQL as root. Set new password. Exit MySQL and restart MySQL server.
# /etc/init.d/mysql stop
# mysqld_safe --skip-grant-tables
# mysql -u root
mysql> use mysql;
mysql> update user set password=PASSWORD("newpassword") where User='root';
mysql> flush privileges;
mysql> quit
# /etc/init.d/mysql stop
# /etc/init.d/mysql start
Set a root password if there is no root password.
# mysqladmin -u root password newpassword
Update a root password.
# mysqladmin -u root -p oldpassword newpassword
Allow the user “Someone” to connect to the server from localhost using the password “passwd”. Login as root. Switch to the MySQL db. Give privs. Update privs.
mysql -u root -p
mysql> use mysql;
mysql> grant usage on \*.\* to Someone@localhost identified by 'passwd';
mysql> flush privileges;
Give user privilages for a db. Login as root. Switch to the MySQL db. Grant privs. Update privs.
mysql -u root -p
mysql> use mysql;
mysql>INSERT INTO user(Host,Db,User,Select_priv,Insert_priv,Update_priv,Delete_priv,Create_priv,Drop_priv)
VALUES ('%','databasename','username','Y','Y','Y','Y','Y','N');
mysql> flush privileges;
or
mysql> grant all privileges on databasename.\* to username@localhost;
mysql> flush privileges;
To update info already in a table.
mysql> UPDATE [table name] SET Select_priv = 'Y',Insert_priv = 'Y',Update_priv = 'Y' where [field name] = 'user';
Delete a row(s) from a table.
mysql> DELETE from [table name] where [field name] = 'fieldvalue';
Update database permissions/privilages.
mysql> flush privileges;
Delete a column.
mysql> alter table [table name] drop column [column name];
Add a new column to db.
mysql> alter table [table name] add column [new column name] varchar (20);
Change column name.
mysql> alter table [table name] change [old column name] [new column name] varchar (50);
Make a unique column so you get no dupes.
mysql> alter table [table name] add unique ([column name]);
Make a column bigger.
mysql> alter table [table name] modify [column name] VARCHAR(3);
Delete unique from table.
mysql> alter table [table name] drop index [colmn name];
Load a CSV file into a table.
mysql> LOAD DATA INFILE '/tmp/filename.csv' replace INTO TABLE [table name] FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n' (field1,field2,field3);
Dump all databases for backup. Backup file is sql commands to recreate all db’s.
# mysqldump -u** **username** **-ppassword --opt > /tmp/alldatabases.sql
Dump one database for backup.
# mysqldump -u username -ppassword --databases databasename > /tmp/databasename.sql
Dump a table from a database.
# mysqldump -u username -ppassword databasename tablename > /tmp/databasename.tablename.sql
Restore database (or database table) from backup.
# mysql -u username -ppassword databasename < /tmp/databasename.sql
Create Table Example 1.
mysql> CREATE TABLE [table name] (name VARCHAR(20));
Create Table Example 2.
mysql> create table [table name] (personid int(50) not null auto_increment primary key,firstname varchar(35),middlename varchar(50),lastnamevarchar(50) default 'somethiing');