You can drop a table group that contains no table (not being referenced by any table).
Prerequisites
Before you drop a table group, query the CDB_OB_TABLEGROUP_TABLES or DBA_OB_TABLEGROUP_TABLES view to check whether the table group contains tables. You can drop only an empty table group. For more information about how to check whether a table group contains tables by using views, see Query information about a table group.
Drop a table group
The SQL syntax for dropping a table group is as follows:
DROP TABLEGROUP [IF EXISTS] tablegroup_name;
Here, tablegroup_name is the name of the table group to be dropped. If the table group to be dropped does not exist and the IF EXISTS clause is not specified, the system returns an error. To execute this statement, you must have the global DROP privilege.
For example, drop the table group tblgroup1.
DROP TABLEGROUP IF EXISTS tblgroup1;