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CompTIA Data+ DA0-002 · Domain 2: Data acquisition and preparation

Query optimization: indexing, filtering early, avoiding SELECT *, subsets and temporary tables

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Last reviewed September 25, 2026 · Leer en español

A query that returns the right answer too slowly is still a problem. Slow queries hold up reports, compete with other users and, in cloud warehouses that bill by data scanned or compute time, cost money. Data+ expects you to know the common ways to make queries faster.

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