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TRUNCATE TABLE cannot be used when a foreign key references the table to be truncated, since TRUNCATE TABLE statements do not fire triggers. This could result in inconsistent data because ON DELETE/ON UPDATE triggers would not fire. In some computer systems, TRUNCATE TABLE resets the count of an Identity column back to the identity's seed.
The DROP statement is distinct from the DELETE and TRUNCATE statements, in that DELETE and TRUNCATE do not remove the table itself. For example, a DELETE statement might delete some (or all) data from a table while leaving the table itself in the database, whereas a DROP statement removes the entire table from the database.
DELETE requires a shared table lock; Triggers fire; DELETE can be used in the case of: database link; DELETE returns the number of records deleted; Transaction log - DELETE needs to read records, check constraints, update block, update indexes, and generate redo / undo. All of this takes time, hence it takes time much longer than with TRUNCATE
TRUNCATE deletes all data from a table in a very fast way, deleting the data inside the table and not the table itself. It usually implies a subsequent COMMIT operation, i.e., it cannot be rolled back (data is not written to the logs for rollback later, unlike DELETE).
A data control language (DCL) is a syntax similar to a computer programming language used to control access to data stored in a database (authorization).In particular, it is a component of Structured Query Language (SQL).
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In SQL, the data manipulation language comprises the SQL-data change statements, [3] which modify stored data but not the schema or database objects. Manipulation of persistent database objects, e.g., tables or stored procedures, via the SQL schema statements, [3] rather than the data stored within them, is considered to be part of a separate data definition language (DDL).