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Indexing Foreign Key Columns for Faster Joins

Creating non-clustered indexes on foreign key columns speeds up relational joins and foreign key validation checks. Database engines use these indexes to avoid full table scans when parent-child records are linked in queries.

snippet.sql

sql

CREATE INDEX idx_orders_customer_id
ON orders (customer_id);

Breakdown

CREATE INDEX idx_orders_customer_id

Declares the creation of a new database index named idx_orders_customer_id.

ON orders (customer_id);

Specifies the target table ('orders') and column ('customer_id') to be indexed.

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Indexing Foreign Key Columns for Faster Joins

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