Question: What Is The Use Of Drop In SQL?

What is the use of drop command in SQL?

The SQL DROP TABLE Statement.

The DROP TABLE statement is used to drop an existing table in a database..

What is difference between drop and delete?

DELETE is a Data Manipulation Language command, DML command and is used to remove tuples/records from a relation/table. Whereas DROP is a Data Definition Language, DDL command and is used to remove named elements of schema like relations/table, constraints or entire schema.

Which is faster truncate or drop?

But TRUNCATE TABLE is faster and uses fewer system and transaction log resources than DELETE. The DELETE statement removes rows one at a time and records an entry in the transaction log for each deleted row. … In the SQL standard, DROP table removes the table and the table schema – TRUNCATE removes all rows.

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.

What is the difference between drop and truncate commands?

The DROP command is used to remove table definition and its contents. Whereas the TRUNCATE command is used to delete all the rows from the table. … DROP is a DDL(Data Definition Language) command. Whereas the TRUNCATE is also a DDL(Data Definition Language) command.

What is the drop table statement?

Use the DROP TABLE statement to move a table or object table to the recycle bin or to remove the table and all its data from the database entirely.

What is the purpose of the IF drop statements?

The DROP TABLE statement deletes the specified table, and any data associated with it, from the database. The IF EXISTS clause allows the statement to succeed even if the specified tables does not exist. If the table does not exist and you do not include the IF EXISTS clause, the statement will return an error.

How do I drop a SQL database?

To delete a databaseIn Object Explorer, connect to an instance of the SQL Server Database Engine, and then expand that instance.Expand Databases, right-click the database to delete, and then click Delete.Confirm the correct database is selected, and then click OK.

Do I need to commit after drop table?

( ALTER FUNCTION can only be used with stored functions.) CREATE TABLE and DROP TABLE statements do not commit a transaction if the TEMPORARY keyword is used. … This means that a ROLLBACK from the user does not undo CREATE TABLE statements the user made during that transaction.

What is rollback commit?

The COMMIT statement commits the database changes that were made during the current transaction, making the changes permanent. … The ROLLBACK statement backs out, or cancels, the database changes that are made by the current transaction and restores changed data to the state before the transaction began.

Why use truncate instead of delete?

TRUNCATE TABLE is faster and uses fewer system resources than DELETE , because DELETE scans the table to generate a count of rows that were affected then delete the rows one by one and records an entry in the database log for each deleted row, while TRUNCATE TABLE just delete all the rows without providing any …

Can we rollback 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.