What is difference TRUNCATE and delete?

The delete statement is used to remove single or multiple records from an existing table depending on the specified condition. The truncate command removes the complete data from an existing table but not the table itself. It preserves the table structure or schema.

What is difference between TRUNCATE DROP and delete explain with example?

DROP and TRUNCATE are DDL commands, whereas DELETE is a DML command. DELETE operations can be rolled back (undone), while DROP and TRUNCATE operations cannot be rolled back.

Why use TRUNCATE instead of delete?

TRUNCATE is faster than DELETE , as it doesn’t scan every record before removing it. TRUNCATE TABLE locks the whole table to remove data from a table; thus, this command also uses less transaction space than DELETE . Unlike DELETE , TRUNCATE does not return the number of rows deleted from the table.

What is rollback in SQL?

ROLLBACK is a transactional control language in SQL. It lets a user undo those transactions that aren’t saved yet in the database. One can make use of this command if they wish to undo any changes or alterations since the execution of the last COMMIT.

Is rollback possible in TRUNCATE?

You cannot ROLLBACK TRUNCATE Simply, you cannot rollback a transaction if it is already committed but you can do something else to get the data back (or at least some parts of it). When you execute the TRUNCATE statement, your data is still in the MDF file.

What is DCL and TCL in SQL?

DCL – Data Control Language. TCL – Transaction Control Language.

What is grant and revoke in SQL?

GRANT & REVOKE are the popular members of the SQL family. These are the types of DCL commands that are used to assign permission to the users to perform a different task. The GRANT command is used for permitting the users whereas the REVOKE command is used for removing the authorization.

What is SAVEPOINT in SQL?

A SAVEPOINT is a point in a transaction when you can roll the transaction back to a certain point without rolling back the entire transaction.

Is TRUNCATE a DDL or DML?

DDL statement
Although TRUNCATE TABLE is similar to DELETE , it is classified as a DDL statement rather than a DML statement. It differs from DELETE in the following ways: Truncate operations drop and re-create the table, which is much faster than deleting rows one by one, particularly for large tables.

What is trigger in SQL?

A trigger is a special type of stored procedure that automatically runs when an event occurs in the database server. DML triggers run when a user tries to modify data through a data manipulation language (DML) event. DML events are INSERT, UPDATE, or DELETE statements on a table or view.