Delete truncate and Drop commands in SQL

Question

What is difference in Drop Delete and Truncate commands in SQL.

Satyapriya Nayak · Answer

Delete command removes the rows from a table based on the condition that we provide with a WHERE clause. Truncate will actually remove all the rows from a table and there will be no data in the table after we run the truncate command. TRUNCATE TRUNCATE is faster and uses fewer system and transaction log resources than DELETE. TRUNCATE removes the data by deallocating the data pages used to store the table's data and only the page deallocations are recorded in the transaction log. TRUNCATE removes all rows from a table but the table structure and its columns constraints indexes and so on remain. The counter used by an identity for new rows is reset to the seed for the column.You cannot use TRUNCATE TABLE on a table referenced by a FOREIGN KEY constraint.Because TRUNCATE TABLE is not logged it cannot activate a trigger. TRUNCATE can not be Rolled back. TRUNCATE is DDL Command. TRUNCATE Resets identity of the table. DELETE DELETE removes rows one at a time and records an entry in the transaction log for each deleted row.If you want to retain the identity counter use DELETE instead. If you want to remove table definition and its data use the DROP TABLE statement. DELETE Can be used with or without a WHERE clause DELETE Activates Triggers. DELETE Can be Rolled back. DELETE is DML Command. DELETE does not reset identity of the table. DROP Removes a table definition and all data indexes triggers constraints and permission specifications for that table. Any view or stored procedure that references the dropped table must be explicitly dropped by using the DROP VIEW or DROP PROCEDURE statement.

Vithal Wadje · Answer

drop command is used to drop the structure of table delete command is used to delete the all records or specific records from table truncate command is used also used to delete all records from table but the difference between delete and truncate is.. you can not be use where clause with Truncate but in delete you can use when you use truncate command to delete the recpords then Rollback is not possible but using delete it is poosible . i hope you have got sufficient answer