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Covering indexes (INCLUDE) and Bitmap Heap Scans — how do you eliminate heap fetches in 2025?

Q: Covering indexes (INCLUDE) and Bitmap Heap Scans — how do you eliminate heap fetches in 2025?

`INCLUDE (col)` adds non-key payload to an index for `Index-Only Scans` without bloating the B-tree. `Bitmap Heap Scan` batches index lookups into sorted TIDs for sequential-ish heap reads — ideal for medium selectivity or `OR` queries. Covering index (INCLUDE) enables Index-Only Scan; Bitmap Heap Scan batches random I/O Covering Index CREATE INDEX ON t(a) INCLUDE (b,c) WHERE a=? needs b,c too avoids heap lookup VACUUM sets VM bit <rect x="300" y="35" w

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Design INCLUDE indexes for index-only scans and understand when bitmap scans batch random I/O.

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INCLUDE (col) adds non-key payload to an index for Index-Only Scans without bloating the B-tree. Bitmap Heap Scan batches index lookups into sorted TIDs for sequential-ish heap reads — ideal for medium selectivity or OR queries.

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