bcquality/microsoft/knowledge/performance/avoid-findfirst-with-next.md
Jesper Schulz-Wedde 9a4198eb28 Add [all] sentinel to bc-version; apply to version-agnostic knowledge
Most of the corpus — FindSet/SetLoadFields/CalcFields patterns, permission
sets, SingleInstance codeunits, DataClassification, IsolatedStorage,
transaction scope, SecretText — describes BC platform behaviour that is
identical across supported versions. The seed [26..28] range on every
file implied a version-specificity the content does not actually have,
and there was no way to express "applies to every version" in the
schema the way [w1] and [all] already do for countries and
application-area.

Extend the v1 schema with a universal sentinel for bc-version, parallel
to the sentinels already defined for the other dimensions:

  bc-version: [all]         # applies to every BC version

[all] is mutually exclusive with explicit versions. Range shorthand
([26..28]) and explicit lists ([26, 27, 28]) continue to work for files
genuinely tied to a version-gated API or deprecation.

Update read.md (field definition, matching semantics, partial-context
rule), write.md (default to [all], use ranges only with a concrete
reason), README.md (frontmatter example), and the CI validator. All
forty existing knowledge files and the three action skills convert to
[all]; none of the current content is version-gated. Validator passes.
2026-04-23 16:00:03 +02:00

25 lines
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Markdown

---
bc-version: [all]
domain: performance
keywords: [findfirst, findlast, get, next, aa0233]
technologies: [al]
countries: [w1]
application-area: [all]
---
# Do not pair FindFirst, FindLast, or Get with Next
## Description
CodeCop rule AA0233 flags loops that start with FindFirst, FindLast, or Get and then call Next. FindFirst and FindLast retrieve a single row and reposition the cursor; calling Next after them forces the platform to re-seek and stream the rest of the set, which is slower than the correct FindSet pattern and signals intent incorrectly to reviewers and the optimizer.
## Best Practice
Choose the Find variant that matches the operation: FindSet for full iteration, FindFirst or FindLast when you want exactly one row, Get when the primary key is known. Never call Next after FindFirst, FindLast, or Get.
## Anti Pattern
Writing `if Rec.FindFirst() then repeat ... until Rec.Next() = 0` is the canonical AA0233 offender. The loop wastes bandwidth and obscures the author's intent.
See sample: `avoid-findfirst-with-next.bad.al`.