bcquality/microsoft/knowledge/performance/only-fetch-records-you-use.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

1.3 KiB

bc-version domain keywords technologies countries application-area
all
performance
findset
get
aa0175
wasted-fetch
read
al
w1
all

Only fetch records you use

Seed article. Converted from an existing performance-review prompt to bootstrap the BCQuality performance corpus. Domain stewards should expand, restructure, and refine as needed.

Description

CodeCop rule AA0175 flags code that retrieves a record and then does not use it. Every Find, FindSet, FindFirst, FindLast, or Get has a cost: the platform reads rows from SQL, materializes them, and transports them to the AL runtime. A call whose result is never read is wasted work, and on hot tables that work is never free.

Best Practice

Retrieve a record only when you need one or more of its field values. When you only need to know whether at least one row matches a filter, use IsEmpty (see use-isempty-for-existence-checks). When you only need a subset of fields, use SetLoadFields (see use-setloadfields-for-partial-records).

See sample: only-fetch-records-you-use.good.al.

Anti Pattern

Calling FindSet or Get and then ignoring the result, or using it only as a boolean existence test, performs the full fetch and throws the data away.

See sample: only-fetch-records-you-use.bad.al.