Sargable

Write conditions that use indexes.

A sargable query can use indexes. WHERE price * 2 > 100 is not sargable.

-- Sargable: WHERE price > 50
-- Non-sargable: WHERE price * 2 > 100

Sargable indexed, non-sargable not.

Sargable — details

Putting a column in a function breaks the index. WHERE UPPER(name) = 'A' skips the index.

Instead, transform the value on the other side (WHERE name = 'a') or create an index on the expression: CREATE INDEX ON customers (UPPER(name)).

Write a sargable query with WHERE price > 50 (uses index).

Show example solution

SELECT * FROM products WHERE price > 50;

sargable

____ → uses an index

Show answer

sargable → uses an index

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