What is Similarity and Difference Between Truncate and Delete in SQL

Question

Hi What is Similarity and Difference between Truncate and Delete in SQL ?

Jignesh Trivedi · Answer

hi Both used for removing Data from Data base. Diffrence : DELETE is a logged operation on a per row basis. TRUNCATE is also a logged operation but in a different way. TRUNCATE logs the deallocation of the data pages in which the data exists. You cannot TRUNCATE a table that has any foreign key constraints  but you can DELETE those record. TRUNCATE will reset any identity columns to the default seed value whereas DELETE is not. TRUNCATE does not contain Where condition whereas DELETE has Truncate Table is faster than Delete Table Truncate Table cannot activate a trigger. hope this will help you.

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.

Rahul Bhatt · Answer

Similar :: Both Remove data from Table Diffrence :: 1. Delete :: Allowed Condition based Delete. (Use where clause) Trunacter:: not allowed condition based Delete 2. Delete :: Rollback Data Truncate :: not to rollback