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REFRESH MATERIALIZED VIEW(7)                    PostgreSQL 9.5.0 Documentation


NAME

       REFRESH_MATERIALIZED_VIEW - replace the contents of a materialized view


SYNOPSIS

       REFRESH MATERIALIZED VIEW [ CONCURRENTLY ] name
           [ WITH [ NO ] DATA ]


DESCRIPTION

       REFRESH MATERIALIZED VIEW completely replaces the contents of a
       materialized view. The old contents are discarded. If WITH DATA is
       specified (or defaults) the backing query is executed 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.

       CONCURRENTLY and WITH NO DATA may not be specified together.


PARAMETERS

       CONCURRENTLY
           Refresh the materialized view without locking out concurrent
           selects on the materialized view. Without this option a refresh
           which affects a lot of rows will tend to use fewer resources and
           complete more quickly, but could block other connections which are
           trying to read from the materialized view. This option may 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 WHERE clause.

           This option may not be used when the materialized view is not
           already populated.

           Even with this option only one REFRESH at a time may run against
           any one materialized view.

       name
           The name (optionally schema-qualified) of the materialized view to
           refresh.


NOTES

       While the default index for future CLUSTER(7) 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 backing query.


EXAMPLES

       This command will replace the contents of the materialized view called
       order_summary using the query from the materialized view's definition,
       and leave it in a scannable state:

           REFRESH MATERIALIZED VIEW order_summary;

       This command will free storage associated with the materialized view
       annual_statistics_basis and leave it in an unscannable state:

           REFRESH MATERIALIZED VIEW annual_statistics_basis WITH NO DATA;


COMPATIBILITY

       REFRESH MATERIALIZED VIEW is a PostgreSQL extension.


SEE ALSO

       CREATE MATERIALIZED VIEW (CREATE_MATERIALIZED_VIEW(7)), ALTER
       MATERIALIZED VIEW (ALTER_MATERIALIZED_VIEW(7)), DROP MATERIALIZED VIEW
       (DROP_MATERIALIZED_VIEW(7))

PostgreSQL 9.5.0                     2016         REFRESH MATERIALIZED VIEW(7)

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