Medium-Easy Apply RDBMS & SQL Multiple Choice

A query runs slowly. EXPLAIN ANALYZE shows a Sequential Scan on a 10-million-row table for WHERE email = 'alice@example.com'. What is the best fix?

Apply — Tests ability to use knowledge in practical scenarios.

Answer Options

A Add ORDER BY to help the query planner optimize
B Create a B-Tree index on the email column
C Increase the server RAM to fit the table in memory
D Rewrite the query using a subquery

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This question is from the RDBMS & SQL topic (Databases).

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