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What is difference between DELETE and TRUNCATE commands?

If you wish to removes rows basis on condition then we have to use DELETE command while truncate will remove all the rows from a table.

DELETE

  • Delete is a DML command
  • We can use WHERE clause in delete statement.
  • Delete statement delete specific rows if where condition exist.
  • Delete command lock the row when executed, each row in table is locked for deletion.
  • Delete operation are logged individually so delete activates the trigger.
  • Rollback is possible in delete.
  • Delete keeps log so delete is slower then truncate.


TRUNCATE

  • Truncate is DDL command.
  • Truncate command removes all data from the table.
  • Truncate does not keep the logs so it fast then DELETE.
  • Truncate statement is not conditional mean we cannot use WHERE clause in truncate statement.
  • Rollback is not possible.
  • Truncate reset the table to its empty state.




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