[dropcap]S[/dropcap]tructured Query Language or SQL in ABAP CDS or SQL in HANA as we all know is the database language by the use of which we can perform certain operations on the existing database and also we can use this language to create a database.
SQL in CDS Types:
DDL
DDL is abbreviation of Data Definition Language. It is used to create and modify the structure of database objects in database.
CREATE – Creates objects in the database
ALTER – Alters objects of the database
DROP – Deletes objects of the database
TRUNCATE – Deletes all records from a table and resets table identity to initial value.
Read More: CDS Arithmetic Functions; Ceil, Floor, Div (Integer), Division (Dec), Mod, Round; Aggregate Expressions ; MAX, MIN, AVG, SUM, COUNT, Group By Clause, HAVING Clause
DML
DML is abbreviation of Data Manipulation Language. It is used to retrieve, store, modify, delete, insert and update data in database.
SELECT – Retrieves data from a table
INSERT – Inserts data into a table
UPDATE – Updates existing data into a table
DELETE – Deletes all records from a table
Read More: CDS Annotations
DCL
DCL is abbreviation of Data Control Language. It is used to create roles, permissions, and referential integrity as well it is used to control access to database by securing it.
GRANT – Gives user’s access privileges to database
REVOKE – Withdraws user’s access privileges to database given with the GRANT command
TCL
TCL is abbreviation of Transactional Control Language. It is used to manage different transactions occurring within a database.
COMMIT – Saves work done in transactions
ROLLBACK – Restores database to original state since the last COMMIT command in transactions
SAVE TRANSACTION – Sets a savepoint within a transaction
