Monday, April 15, 2019

Basic SQL

SQL means "Structured Query Language". SQL is the mother of all the relational database languages. It is used to create, maintain and retrieve Relational Databases. It is used to insert, update and delete the Relational Databases.

 All the functions in sql comes under this category called as DDL, DML, DCL & TCL.
Let me explain one by one 

 Data Definition Language (DDL) : These commands are used to create and modify the structure of database objects in the database.
- Create
- Alter
- Drop

 Data Manupulation Language (DML) : These commands are used to munupulate or edit the database objects in the database.
- Select
- Insert
- Update
- Delete

 Data Control Language (DCL) : These commands are used to deal with permissions and rights of database objects.
- Grant
- Revoke

 Transaction Control Language (TCL) : It is used to handle database transactions.
- Commit
- Rollback
- Save Point





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