what is the difference between Delete and Truncate

Answer Posted / bhaskar

What is difference between DELETE & TRUNCATE commands?
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 using logs.
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 using logs.
DELETE is DML Command.
DELETE does not reset identity of the table.

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