Replaces the contents of a materialized view.
REFRESH MATERIALIZED VIEW [ CONCURRENTLY ] <name> [ WITH [ NO ] DATA ]
REFRESH MATERIALIZED VIEW completely replaces the contents of a materialized view. The old contents are discarded. To run this command you must be the owner of the materialized view. With the default,
WITH DATA, the materialized view query is run to provide the new data, and the materialized view is left in a scannable state. If
WITH NO DATA is specified, no new data is generated and the materialized view is left in an unscannable state. A query returns an error if the query attempts to access the materialized view.
Refresh the materialized view without locking out concurrent selects on the materialized view. Without this option, a refresh that affects a lot of rows tends to use fewer resources and completes more quickly, but could block other connections which are trying to read from the materialized view. This option might be faster in cases where a small number of rows are affected.
This option is only allowed if there is at least one
UNIQUE index on the materialized view which uses only column names and includes all rows; that is, it must not index on any expressions nor include a
This option cannot be used when the materialized view is not already populated, and it cannot be used with the
WITH NO DATA clause.
Even with this option, only one
REFRESH at a time may run against any one materialized view.
WITH DATA is the default and specifies that the materialized view query is run to provide new data, and the materialized view is left in a scannable state. If
WITH NO DATA is specified, no new data is generated and the materialized view is left in an unscannable state. An error is returned if a query attempts to access an unscannable materialized view.
WITH NO DATAcannot be used with
While the default index for future CLUSTER operations is retained,
REFRESH MATERIALIZED VIEW does not order the generated rows based on this property. If you want the data to be ordered upon generation, you must use an
ORDER BY clause in the materialized view query. However, if a materialized view query contains an
ORDER BY or
SORT clause, the data is not guaranteed to be ordered or sorted if
SELECT is performed on the materialized view.
This command replaces the contents of the materialized view
order_summary using the query from the materialized view's definition, and leaves it in a scannable state.
REFRESH MATERIALIZED VIEW order_summary;
This command frees storage associated with the materialized view
annual_statistics_basis and leaves it in an unscannable state.
REFRESH MATERIALIZED VIEW annual_statistics_basis WITH NO DATA;
REFRESH MATERIALIZED VIEW is a Greenplum Database extension of the SQL standard.
Parent topic: SQL Commands