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Documentation Index

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Syntax

ALTER INDEX index_name
    alter_option;
alter_option depends on the operation you want to perform on the index. For all supported clauses, see the sections below.

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Clause

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RENAME TO

ALTER INDEX index_name
    RENAME TO new_name;
Parameter or clauseDescription
RENAME TOThis clause changes the name of the index. If the index is associated with a table constraint (either UNIQUE, PRIMARY KEY, or EXCLUDE), the constraint is renamed as well. There is no effect on the stored data.
new_nameThe new name of the index.
-- Change the name of the index "idx_1" to "idx_2"
ALTER INDEX idx_1 RENAME TO idx_2.

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SET PARALLELISM

ALTER INDEX index_name
SET PARALLELISM { TO | = } parallelism_number;
Parameter or clauseDescription
SET PARALLELISMThis clause controls the degree of parallelism for the targeted streaming job.
parallelism_numberCan be ADAPTIVE or a fixed number (e.g., 1, 2, 3). Setting it to ADAPTIVE expands the job’s parallelism to all available units, while a fixed number locks it at that value. Setting it to 0 is equivalent to ADAPTIVE. The maximum allowed value is determined by the max_parallelism of the job. For more information, see Configuring maximum parallelism.
-- Set the parallelism of the index "idx_orders" to 3.
ALTER INDEX idx_orders SET PARALLELISM = 3;

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SET BACKFILL_PARALLELISM

ALTER INDEX index_name
    SET BACKFILL_PARALLELISM { TO | = } parallelism_value [ DEFERRED ];
This statement controls the degree of parallelism used during the backfill phase of an index. It lets you tune resource usage for backfilling independently from the index’s steady-state parallelism.
Parameter or clauseDescription
SET BACKFILL_PARALLELISMSets the parallelism for the backfill phase of the streaming job.
parallelism_valueCan be ADAPTIVE or a fixed number (e.g., 1, 2, 3). Setting it to ADAPTIVE or 0 expands backfill parallelism to all available units. A fixed number locks it at that value.
DEFERREDOptional. When specified, the change takes effect after the current backfill completes, without interrupting an ongoing backfill. If omitted, the change is applied immediately.
-- Set backfill parallelism to a fixed value
ALTER INDEX idx_orders SET BACKFILL_PARALLELISM = 4;

-- Set backfill parallelism to adaptive
ALTER INDEX idx_orders SET BACKFILL_PARALLELISM = ADAPTIVE;

-- Defer the parallelism change until the current backfill completes
ALTER INDEX idx_orders SET BACKFILL_PARALLELISM = 4 DEFERRED;