There are 4 types of languages in the relational database.
They are –
- DDL(Data Definition Language)
- DML(Data Manipulation Language)
- TCL(Transaction Control Language)
- DCL(Data Control Language)
DDL
This language is basically used to create new databases, tables ;rename tables; drop databases and tables; truncate table means remove all existing records from table; rollback a table from recycle bin.
lets understood DDL commands –
CREATE – this command used to create database or even create table inside database
RENAME – this command used to rename table inside database
DROP – this command used to drop (delete) database and tables from database also
TRUNCATE – this command used to remove existing records from table
ROLLBACK – this command helps to recover table from recycle bin into database
DML
This language is basically used to insert, delete, update and view records inside a table into a database.
INSERT – this command used to insert record inside table in relational database
UPDATE – this command used to update record inside table in relational database
DELETE – this command used to delete record from table
SELECT – this command used to view all the existing record from table
DCL
This language is used to provide permission to users in databases.
GRANT – this command provide permission to any user by database administrator
REVOKE – this command uses to revoke permissions from any user into database
TCL
When any transaction occurs into the database, sometimes we need to commit that to stay the effect into the database.
For this we need to use TCL. There are some TCL commands into relational databases.
COMMIT – this command used to commit operation which happens into database table
ROLLBACK – this command used to rollback operations from the database.
To understand these use cases I would strongly recommend you to visit after operations with these commands into MySQL database.
For exam purposes I would suggest you, only read the theories above it would help to make a solid building block for you.