Handy MySQL Commands

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    Using MySQL commands can be useful in an environment where graphical user interfaces like MySql Workbench and PhpMyAdmin may not be available and only Unix like environment is there. There comes this handy guide of most commonly used MySql operation commands by which you can completely control the MySql Server database through command line interface (CLI). In this post you will see list of commands for MySql.

    Description Command
    To login (from unix shell) use -h only if needed. [mysql dir]/bin/mysql -h hostname -u root -p
    Create a database on the sql server. create database [databasename];
    List all databases on the sql server. show databases;
    Switch to a database. use [db name];
    To see all the tables in the db. show tables;
    To see database’s field formats. describe [table “” not found /]
    ;
    To delete a db. drop database [database name];
    To delete a table. drop table [table “” not found /]
    ;
    Show all data in a table. SELECT * FROM [table “” not found /]
    ;
    Returns the columns and column information pertaining to the designated table. show columns from [table “” not found /]
    ;
    Show certain selected rows with the value “whatever”. SELECT * FROM [table “” not found /]
    WHERE [field name] = “whatever”;
    Show all records containing the name “Bob” AND the phone number ‘3444444’. SELECT * FROM [table “” not found /]
    WHERE name = “Bob” AND phone_number = ‘3444444’;
    Show all records not containing the name “Bob” AND the phone number ‘3444444’ order by the phone_number field. SELECT * FROM [table “” not found /]
    WHERE name != “Bob” AND phone_number = ‘3444444’ order by phone_number;
    Show all records starting with the letters ‘bob’ AND the phone number ‘3444444’. SELECT * FROM [table “” not found /]
    WHERE name like “Bob%” AND phone_number = ‘3444444’;
    Use a regular expression to find records. Use “REGEXP BINARY” to force case-sensitivity. This finds any record beginning with a. SELECT * FROM [table “” not found /]
    WHERE rec RLIKE “^a$”;
    Show unique records. SELECT DISTINCT [column name] FROM [table “” not found /]
    ;
    Show selected records sorted in an ascending (asc) or descending (desc). SELECT [col1],[col2] FROM [table “” not found /]
    ORDER BY [col2] DESC;
    Count rows. SELECT COUNT(*) FROM [table “” not found /]
    ;
    Join tables on common columns. select lookup.illustrationid, lookup.personid,person.birthday from lookup
    left join person on lookup.personid=person.personid=statement to join birthday in person table with primary illustration id;
    Switch to the mysql db. Create a new user. INSERT INTO [table “” not found /]
    (Host,User,Password) VALUES(‘%’,’user’,PASSWORD(‘password’));
    Change a users password.(from unix shell). [mysql dir]/bin/mysqladmin -u root -h hostname.blah.org -p password ‘new-password’
    Change a users password.(from MySQL prompt). SET PASSWORD FOR ‘user’@’hostname’ = PASSWORD(‘passwordhere’);
    Switch to mysql db.Give user privilages for a db. INSERT INTO [table “” not found /]
    (Host,Db,User,Select_priv,Insert_priv,Update_priv,Delete_priv,Create_priv,Drop_priv) VALUES (‘%’,’db’,’user’,’Y’,’Y’,’Y’,’Y’,’Y’,’N’);
    To update info already in a table. UPDATE [table “” not found /]
    SET Select_priv = ‘Y’,Insert_priv = ‘Y’,Update_priv = ‘Y’ where [field name] = ‘user’;
    Delete a row(s) from a table. DELETE from [table “” not found /]
    where [field name] = ‘whatever’;
    Update database permissions/privilages. FLUSH PRIVILEGES;
    Delete a column. alter table [table “” not found /]
    drop column [column name];
    Add a new column to db. alter table [table “” not found /]
    add column [new column name] varchar (20);
    Change column name. alter table [table “” not found /]
    change [old column name] [new column name] varchar (50);
    Make a unique column so you get no dupes. alter table [table “” not found /]
    add unique ([column name]);
    Make a column bigger. alter table [table “” not found /]
    modify [column name] VARCHAR(3);
    Delete unique from table. alter table [table “” not found /]
    drop index [colmn name];
    Load a CSV file into a table. LOAD DATA INFILE ‘/tmp/filename.csv’ replace INTO TABLE [table “” not found /]
    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. [mysql dir]/bin/mysqldump -u root -ppassword –opt >/tmp/alldatabases.sql
    Dump one database for backup. [mysql dir]/bin/mysqldump -u username -ppassword –databases databasename >/tmp/databasename.sql
    Dump a table from a database. [mysql dir]/bin/mysqldump -c -u username -ppassword databasename tablename > /tmp/databasename.tablename.sql
    Restore database (or database table) from backup. [mysql dir]/bin/mysql -u username -ppassword databasename < /tmp/databasename.sql
    Create Table Example 1. CREATE TABLE [table “” not found /]
    (firstname VARCHAR(20), middleinitial VARCHAR(3), lastname VARCHAR(35),suffix VARCHAR(3),
    officeid VARCHAR(10),userid VARCHAR(15),username VARCHAR(8),email VARCHAR(35),phone VARCHAR(25), groups
    VARCHAR(15),datestamp DATE,timestamp time,pgpemail VARCHAR(255));
    Create Table Example 2. create table [table “” not found /]
    (personid int(50) not null auto_increment primary key,firstname varchar(35),middlename varchar(50),lastname varchar(50) default ‘bato’);