TRUNCATE is a DDL command whereas DELETE is a DML command. 
Hence DELETE operation can be rolled back, but TRUNCATE 
operation cannot be rolled back. WHERE clause can be used 
with DELETE and not with TRUNCATE.

delete table gives the transactional log where as in 
truncate it is not delete the total rows inthe table but 
structure of the table has never changed after the 
statement is executed it is roll back and the constraints 
after the delete statement is remain same where as it is 
not in the truncate statement

"Delete TableName" is a logged transaction.  Every row 
affected by the delete will be written to the transaction 
log.  This is done for RECOVERY purposes, so that the 
transaction may be rolled forward from a previous database 
dump.

"Truncate TableName" is non-logged.  It removes all rows 
from the table and releases all allocated segments in the 
database, all without logging anything.  This is not 
something a developer does, but rather is done by a DBA as 
part of some sort of housekeeping.

1.truncate is DDL cmd.where as delete is a DML cmd.
2.truncate  is similar to delete command without no 
condition.
3.when u use truncate it restructure the table,wthout 
bothering of data it deletes entire records.
      but,delete is a logged transaction.before delete 
records it copies to transaction log.then removes.
4.truncate take less time than delete in execution.

Truncate is DDL command, Delete is a DML command.
Delete operation can be rolled back and in truncate we 
can't.
Where caluse can be used in Delete and not in Truncate.
Truncate table less time than delete in execution

Truncate / When use Truncate after that insert new record 
into the table row started from 1 but
 Delete / When delete record in a table after that insert 
new record row id started from after the deleted row
For e g, I m create a table Employee and insert 5 record 
row number set identity true and increment by 1 
After that, I m delete last record I e row number is 5 
after delete I m insert new record in a table then row id 
started from 6 not 5 but when truncate table row id start 
from 1

1.Both Truncate and Delete are rollbacked in TSQL.
2.Truncate maintains single record in Transaction log   
entire records where Delete writes one-to-one record which 
is slow in performance.
3.Truncate reinitializes the IDENTITY count to zero.
4.Truncate gives error with Table Variables.

DELETE Command
•It will delete record by record             

•Execution is slow                               
•It is a logged command, so data
 can be Restore after delete
•Condition can be applied with delete.
•It will fire trigger.                                    

TRUNCATE Command
•It will delete all the records at the Same time.
•Execution is fast.
•It is not a logged command, so data can’t
 be Restore after Truncate.
•Condition can’t be applied.
•It will not fire the trigger.

ajay.thomala@gmail.com

TRUNCATE is a DDL command whereas DELETE is a DML command. 
Hence DELETE operation can be rolled back, but TRUNCATE 
operation cannot be rolled back. WHERE clause can be used 
with DELETE and not with TRUNCATE.