a9f3c50863
The previous LLM-generated knowledge files contained factual
hallucinations. The most visible was the claim that `FindFirst` /
`FindLast` "forces a full-table scan" on an unfiltered record - it does
not; those APIs return a single row via the current key.
Other inaccuracies the audit found and fixed:
* `FindSet(true)` was described as "taking a LockTable". The correct
upstream phrasing is that `FindSet(true)` sets
`ReadIsolation::UpdLock` on the read. UpdLock and LockTable are
related but distinct mechanisms.
* The list of production-scale tables had been invented beyond the
upstream source (e.g. "Detailed Cust. Ledg. Entry") without a
citation. The regenerated list matches the ten tables upstream lists
with their P95 row counts.
* `SetLoadFields` guidance had been augmented with an extra mechanism
claim ("the database resolves the filter using the index without
hydrating the value") not present in upstream.
Approach: full regeneration of `microsoft/knowledge/` from the six
upstream BCApps Code Review instruction files, with Microsoft Learn /
the AL language reference as a secondary source. Every claim in every
regenerated file is anchored to a verbatim upstream quote (or a Learn
URL); the audit trail lives in artifacts/trace-<domain>.json on the
session workspace.
The PR #11 transaction/error-handling cluster is preserved verbatim:
* performance/understand-implicit-transaction-boundary.md
* performance/codeunit-run-as-atomic-sub-operation.{md,good.al,bad.al}
* performance/codeunit-run-requires-prior-commit-inside-transaction.{md,good.al,bad.al}
* performance/use-tryfunction-for-error-catching-not-rollback.{md,good.al,bad.al}
* performance/avoid-commit-inside-loops.{md,good.al,bad.al}
* security/commitbehavior-attribute-scopes-explicit-commits.{md,good.al,bad.al}
* testing/transactionmodel-attribute-governs-test-transactions.{md,good.al,bad.al}
These articles already cite Microsoft Learn and were carefully
cross-referenced; the regeneration skips their topics rather than
duplicating them.
File counts after regeneration:
performance 35 .md (5 preserved + 30 new)
privacy 17 .md
security 18 .md (1 preserved + 17 new)
style 33 .md
testing 1 .md (preserved)
ui 19 .md
upgrade 18 .md
Total 141 atomic knowledge files, each strictly one rule. All pass
.github/scripts/validate_frontmatter.py with 0 errors and 0 warnings.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
1.9 KiB
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A FlowField needs a source-table key that covers its CalcFormula
Description
A FlowField is computed by SQL on demand. CodeCop AA0232 — "FlowFields should be indexed with SumIndexFields on corresponding keys" — captures the indexing requirement: the source table must declare a key that includes the fields the CalcFormula filters on, with the aggregated field listed in that key's SumIndexFields. When that alignment is in place, the platform answers CalcFields/CalcSums from SIFT; without it, the same query falls back to a row-by-row aggregation on what is often a ledger-scale table. Per the upstream guidance, "Missing SIFT indices cause performance issues on List pages."
Best Practice
When introducing or changing a FlowField, walk the CalcFormula's WHERE clause field by field and verify the source table has a key whose key fields cover those filters, with the aggregated field in SumIndexFields. The same applies when the destination side of the FlowField filter is a list-page column: the page filter triggers the FlowField on every visible row, and only SIFT keeps that affordable.
See sample: flowfield-source-key-needs-sumindexfields.good.al.
Anti Pattern
A sum FlowField against a large source table with no matching SIFT key. Each calculation aggregates rows directly; on a ledger-sized source the FlowField becomes the slowest column on every page that displays it. Pointing an existing FlowField's CalcFormula at a larger source table without verifying the new source's keys is the same trap a step removed — the upstream review guidance flags it as "CalcFormula changed to larger source table".
See sample: flowfield-source-key-needs-sumindexfields.bad.al.