| Handy MySQL Commands |
| 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 name]; |
| To delete a db. | drop database [database name]; |
| To delete a table. | drop table [table name]; |
| Show all data in a table. | SELECT * FROM [table name]; |
| Returns the columns and column information pertaining to the designated table. | show columns from [table name]; |
| Show certain selected rows with the value "whatever". | SELECT * FROM [table name] WHERE [field name] = "whatever"; |
| Show all records containing the name "Bob" AND the phone number '3444444'. | SELECT * FROM [table name] 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 name] 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 name] WHERE name like "Bob%" AND phone_number = '3444444'; |
| Use a regular expression to find records. Use "REGEXPBINARY" to force case-sensitivity. This finds any record beginning witha. | SELECT * FROM [table name] WHERE rec RLIKE "^a$"; |
| Show unique records. | SELECT DISTINCT [column name] FROM [table name]; |
| Show selected records sorted in an ascending (asc) or descending (desc). | SELECT [col1],[col2] FROM [table name] ORDER BY [col2] DESC; |
| Count rows. | SELECT COUNT(*) FROM [table name]; |
| 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 name] (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. | INSERTINTO [table name](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 name] SET Select_priv = 'Y',Insert_priv = 'Y',Update_priv = 'Y' where [field name] = 'user'; |
| Delete a row(s) from a table. | DELETE from [table name] where [field name] = 'whatever'; |
| Update database permissions/privilages. | FLUSH PRIVILEGES; |
| Delete a column. | alter table [table name] drop column [column name]; |
| Add a new column to db. | alter table [table name] add column [new column name] varchar (20); |
| Change column name. | alter table [table name] change [old column name] [new column name] varchar (50); |
| Make a unique column so you get no dupes. | alter table [table name] add unique ([column name]); |
| Make a column bigger. | alter table [table name] modify [column name] VARCHAR(3); |
| Delete unique from table. | alter table [table name] drop index [colmn name]; |
| Load a CSV file into a table. | 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. | [mysql dir]/bin/mysqldump --user=root --password=blah --all-databases >/tmp/sql-01_backup.sql |
| Create Table Example 1. | CREATE TABLE [table name] (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 1. | CREATE TABLE [table name] (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)); |
| If you want to change a column's type but not the name, CHANGE syntax still requires an old and new column name, even if they are the same. | ALTER TABLE TblName CHANGE ColName ColName BIGINT NOT NULL; |
