8. SQL Statements : DROP : Description
 
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Description
The DROP statement removes the specified tables, indexes, or views from the database. Any synonyms and comments defined for the specified object are also dropped. If the object is a table, any indexes, views, privileges, and integrities defined on that table are automatically dropped.
If an object type is not specified, Ingres assumes you are dropping a table, view, or index.
If the IF EXISTS clause is used and the specified object exists, Ingres drops it; if the specified object does not exist or exists but is not owned by you, Ingres does not return an error message. The IF EXISTS clause is typically used prior to issuing the corresponding CREATE statement to ensure that the CREATE statement does not fail due to an existing object of that type.
If the keyword indicating the object type is specified, the DBMS Server checks to make sure that the object named is the specified type. If more than one object is listed, only objects of the specified type are dropped. For example, if employee is a base table and emp_sal is a view on the base table salary, the following statement:
DROP TABLE employee, emp_sal;
drops only the employee base table (because the keyword TABLE was specified and emp_sal is a view, not a base table).
To drop a combination of table, views, and indexes in a single statement, omit the objecttype keyword. For example:
DROP employee, emp_sal;
If an object that is used in the definition of a database procedure is dropped, all permits on the procedure are dropped (the procedure is not dropped). The procedure cannot be executed, nor can the execute privilege be granted on the procedure until all the objects required by its definition exist.
All temporary tables are deleted automatically at the end of the session.