DROP INDEX — remove an index
DROP INDEX name
[, ...] [ CASCADE | RESTRICT ]
DROP INDEX
drops an existing index from the database
system. To execute this command you must be the owner of
the index.
name
The name (optionally schema-qualified) of an index to remove.
CASCADE
Automatically drop objects that depend on the index.
RESTRICT
Refuse to drop the index if any objects depend on it. This is the default.