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Move canonical knowledge for Microsoft-owned review domains into the Microsoft layer and document the skill/knowledge co-location policy. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 2a6ea875-d38e-4f30-aadb-0d606f9be231
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Query results bypass the primary-key cache
Contributions welcome — open a PR to refine or extend this article.
Description
The Business Central server caches primary-key Get calls within a transaction. Query objects do not use that cache: every Open/Read goes to SQL. avoid-get-inside-loop-on-large-table.md is right when an unbounded inner Get/FindFirst joins two large sets. It is wrong as a blanket rewrite of repeated Get on the same keys. Replacing a cached Get with a Query that re-executes per call can be slower. This file exists so reviewers stop treating every Get inside a loop as a Query candidate.
Best Practice
Keep Record.Get for repeated lookups of the same primary keys in one transaction. Use a Query when the work is a true join or aggregation that the record API would express as nested scans. Do not flag a guarded Get on a repeating key as an N+1 solely because a Query could express the same columns.
See sample: query-results-bypass-primary-key-cache.good.al.
Anti Pattern
Rewriting a helper that Gets Customer by No. on every sales line into a Query opened inside that helper. Distinct line customers still need a lookup; repeating customers were already served from the PK cache. The Query pays SQL every time.
See sample: query-results-bypass-primary-key-cache.bad.al.