move_chunk function acts like a combination of the
CLUSTER command and
ALTER TABLE…SET TABLESPACE commands. Unlike
these commands, however, the move_chunk function uses lower lock
levels so that the and are able to be read for most of the
process. This comes at a cost of slightly higher disk usage during the
operation. For a more detailed discussion of this capability, see the
documentation on managing storage with tablespaces.
You must be logged in as a super user, such as the
postgres user,
to use the move_chunk() call.