Vol. I · A Postgres HandbookTwelve chapters · · 756 queries

The Query & the Schema

A reading-room reference for writing PostgreSQL by hand — selects to window functions, with the schema in plain view.

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Chapters · Performance & Indexes · Query 023 / 076
AdvancedPerformance & Indexes

Create a Partial Index

The query

SQL
CREATE INDEX idx_active_employees 
ON employees (last_name) 
WHERE status = 'active';
Tested against PostgreSQL 16

Note

“Indexes only a subset of data. Much smaller and faster to update than a full index. Perfect for soft-deletes or status flags.

Tables referenced

  • employees10 cols

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Create a multi-column (composite) index

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The Query & the Schema

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Compiled for Postgres 16 · MMXXVI