292bdabe27
Pure git-mv relocation of all 7 performance articles from community/knowledge/performance/ to microsoft/knowledge/performance/. No content changes. Co-authored-by: Jesper Schulz-Wedde <jesper.schulzwedde@microsoft.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Load common fields before branching on case
Contributions welcome — open a PR to refine or extend this article.
Description
When record processing branches on state, different branches typically read different fields. A single SetLoadFields at the top listing every field any branch might touch pulls more data than any individual execution path needs — on the hot path, the rest is loaded for nothing. A two-tier approach matches loading to actual usage: load the fields the case expression evaluates plus any fields every branch uses, then add a branch-local SetLoadFields inside each branch for that branch's extra fields.
Best Practice
Before the case, call SetLoadFields with the minimal set — the discriminator field and fields common to every branch. Inside each branch, before the first access to a branch-specific field, add a second SetLoadFields covering those fields. The platform honors the in-branch call for the next record operation, so the extra data is fetched only when the branch runs.
See sample: load-common-fields-before-branching-on-case.good.al.
Anti Pattern
A single top-level SetLoadFields enumerating every field any branch might read. On records whose state routes them to the fast common branch, the rarely-needed fields are still loaded — the optimization becomes a net-neutral or net-negative change on the hot path.
See sample: load-common-fields-before-branching-on-case.bad.al.