DROP [TEMPORARY] TABLE [IF EXISTS]
tbl_name [, tbl_name] ...
[RESTRICT | CASCADE]
DROP TABLE
removes one or more
tables. You must have the DROP
privilege for each table.
Be careful with this statement! For each table, it removes the table definition and all table data. If the table is partitioned, the statement removes the table definition, all its partitions, all data stored in those partitions, and all partition definitions associated with the dropped table.
Dropping a table also drops any triggers for the table.
DROP TABLE
causes an implicit
commit, except when used with the TEMPORARY
keyword. See Section 15.3.3, “Statements That Cause an Implicit Commit”.
When a table is dropped, privileges granted specifically for the table are not automatically dropped. They must be dropped manually. See Section 15.7.1.6, “GRANT Statement”.
If any tables named in the argument list do not exist,
DROP TABLE
behavior depends on
whether the IF EXISTS
clause is given:
Without
IF EXISTS
, the statement fails with an error indicating which nonexisting tables it was unable to drop, and no changes are made.With
IF EXISTS
, no error occurs for nonexisting tables. The statement drops all named tables that do exist, and generates aNOTE
diagnostic for each nonexistent table. These notes can be displayed withSHOW WARNINGS
. See Section 15.7.7.42, “SHOW WARNINGS Statement”.
IF EXISTS
can also be useful for dropping
tables in unusual circumstances under which there is an entry in
the data dictionary but no table managed by the storage engine.
(For example, if an abnormal server exit occurs after removal of
the table from the storage engine but before removal of the data
dictionary entry.)
The TEMPORARY
keyword has the following
effects:
The statement drops only
TEMPORARY
tables.The statement does not cause an implicit commit.
No access rights are checked. A
TEMPORARY
table is visible only with the session that created it, so no check is necessary.
Including the TEMPORARY
keyword is a good way
to prevent accidentally dropping non-TEMPORARY
tables.
The RESTRICT
and CASCADE
keywords do nothing. They are permitted to make porting easier
from other database systems.
DROP TABLE
is not supported with
all innodb_force_recovery
settings. See Section 17.21.3, “Forcing InnoDB Recovery”.