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9.2.3|16.5k
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  • ALTER
  • ALTER COLUMN (TABLE)
  • ADD INDEX

ALTER TABLE COLUMN ADD INDEX

Indexes an existing symbol column.

Syntax​

Flow chart showing the syntax of the ALTER TABLE ALTER COLUMN ADD INDEX keyword

Adding an index is an atomic, non-blocking, and non-waiting operation. Once complete, the SQL optimizer will start using the new index for SQL executions.

Example​

Adding an index
ALTER TABLE trades ALTER COLUMN instrument ADD INDEX;
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