REINDEX { TABLE | DATABASE | INDEX } name [ FORCE ]
Recreate all indexes of a specified table.
Recreate all system indexes of a specified database.
Recreate a specified index.
The name of the specific table/database/index to be be reindexed.
Recreate indexes forcedly. Without this keyword REINDEX does nothing unless target indexes are invalidated.
REINDEX is used to recover corrupted system indexes. In order to run REINDEX command, postmaster must be shut down and stand-alone Postgres should be started instead with options -O and -P (an option to ignore system indexes). Note that we couldn't rely on system indexes for the recovery of system indexes.