When to Use a Composite SQL Index
A query filters on several fields, but separate single-column indexes do not always serve the combined access pattern well. This guide gives you a small, testable way to approach the issue before changing a live system.
A practical workflow
- List the equality filters, range condition and sort order from the frequent query.
- Test a multi-column index with equality columns first and inspect the actual plan using realistic data.
What to check
Column order matters and an index tailored to one query may not help another; measure write costs too. Compare the result with the original problem and record what changed. If a measurement or test does not support the change, revisit the assumption rather than adding more complexity.
Keep the experiment small enough to reverse. Document the starting state, the change and the result so another person can repeat the process. Product menus and versions can change, so check the current documentation for your environment.
Official reference: Read the documentation.