ALTER MATERIALIZED VIEW

The ALTER MATERIALIZED VIEW command modifies the metadata of a materialized view. To use this command, you must own the materialized view.

INFO

To modify the SQL definition of a materialized view, please refer to Alter a streaming job.

Syntax

ALTER MATERIALIZED VIEW materialized_view_name
    alter_option;

alter_option depends on the operation you want to perform on the materialized view. For all supported clauses, see the sections below.

Clause

OWNER TO

ALTER MATERIALIZED VIEW materialized_view_name
    OWNER TO new_user;

Parameter or clause	Description
OWNER TO	This clause changes the owner of the materialized view. Note that this will cascadingly change all related internal objects as well.
new_user	The new owner you want to assign to the materialized view.

-- Change the owner of the materialized view named "materialized_view1" to user "user1"
ALTER MATERIALIZED VIEW materialized_view1 OWNER TO user1;

SET SCHEMA

ALTER MATERIALIZED VIEW materialized_view_name
    SET SCHEMA schema_name;

Parameter or clause	Description
SET SCHEMA	This clause moves the materialized view to a different schema.
schema_name	The name of the schema to which the materialized view will be moved.

-- Move the materialized view named "test_materialized_view" to the schema named "test_schema"
ALTER MATERIALIZED VIEW test_materialized_view SET SCHEMA test_schema;

SET PARALLELISM

ALTER MATERIALIZED VIEW materialized_view_name
SET PARALLELISM = parallelism_number;

Parameter or clause	Description
SET PARALLELISM	This clause controls the degree of parallelism for the targeted streaming job.
parallelism_number	This parameter can be ADAPTIVE or a fixed number, like 1, 2, 3, etc. Altering the parameter to ADAPTIVE will expand the streaming job’s degree of parallelism to encompass all available units, whereas setting it to a fixed number will lock the job’s parallelism at that specific figure. Setting it to 0 is equivalent to ADAPTIVE.

-- Set the parallelism of the materialized view "m_join" to 3.
ALTER MATERIALIZED VIEW m_join SET PARALLELISM = 3;

RENAME TO

ALTER MATERIALIZED VIEW materialized_view_name
    RENAME TO new_name;

Parameter or clause	Description
RENAME TO	This clause changes the name of the materialized view.
new_name	The new name of the materialized view.

-- Change the name of the materialized view named "mv_1" to "mv_2"
ALTER MATERIALIZED VIEW mv_1 RENAME TO mv_2;

SET BACKFILL_RATE_LIMIT

ALTER MATERIALIZED VIEW mv_name
    SET BACKFILL_RATE_LIMIT { TO | = } { default | rate_limit_number };

This statement controls the rate limit of a newly created materialized view’s backfilling process from upstream materialized views and sources. For the specific value of BACKFILL_RATE_LIMIT, refer to How to view runtime parameters.

Examples

-- Pause the backfill
ALTER MATERIALIZED VIEW mv1 SET BACKFILL_RATE_LIMIT=0;

-- Set backfill rate limit to 1
ALTER MATERIALIZED VIEW mv1 SET BACKFILL_RATE_LIMIT=1;

-- Disable the backfill
ALTER MATERIALIZED VIEW mv1 SET BACKFILL_RATE_LIMIT=DEFAULT;

To modify the rate limit of the sources used in the materialized view, please refer to SET SOURCE_RATE_LIMIT.

SWAP WITH

ALTER MATERIALIZED VIEW name
SWAP WITH target_name;

Parameter	Description
name	The current name of the materialized view to swap.
target_name	The target name of the materialized view you want to swap with.

-- Swap the names of the sales_summary materialized view and the sales_archive materialized view.
ALTER MATERIALIZED VIEW sales_summary
SWAP WITH sales_archive;