1 . Data Definition Language ( DDL )
Data Definition Language ( DDL ) is a sub- language of SQL that is used to build a database framework . There are three commands that are included in the DDL , namely :
- CREATE : This command is used to create , including creating a new database , new tables , new views , and columns .
- ALTER : This command is used to change the table structure that has been created . Work includes replacing the name of the table , add columns , change the column , remove the column , or to attribute to the column .
- DROP : This command is used to delete the database and tables .
2 . Data Manipulation Language ( DML )
Data Manipulation Language ( DML ) is a sub- language of SQL is used to manipulate data in a database that has been made ??. Commands are used , including :
- INSERT : This command is used to insert or insert new data into the table . Database and table use after completion.
- SELECT : This command is used to retrieve the data or display data from a table or tables in the relationship . The data is taken we can show the SQL prompt screen directly and shown on the display application .
- UPDATE : This command is used to update the old data to current data . If you have data that is incorrect or not up to date with current conditions , the contents of the data can be changed using the UPDATE command .
- DELETE : This command is used to delete data from a table . Usually the deleted data is data that is not needed anymore . At the time of deleting the data , command history can not be defeated , so the data that has been lost can not be restored anymore .
3 . Data Control Language ( DCL )
Data Control Language ( DCL ) is a sub- language of SQL is used for controlling the data and the database server . DCL commands , including :
- GRANT : This command is used to grant / permit access by the administrator ( principal owner ) server to the user ( regular user ) . Rights such as the right to make such access ( CREATE ) , take ( SELECT ) , delete ( DELETE ) , change ( UPDATE ) , and the special rights relating to the database system .
- REVOKE : This command has reversed with GRAND usability , which is to eliminate or revoke permissions that have been granted to the user by the administrator .
Comments
Post a Comment