Update 6 knowledge articles to align with revised instructions

- performance/use-setloadfields-for-partial-records: Clarify that
  filter-only fields (SetRange/SetFilter) do not need to be listed in
  SetLoadFields — the DB resolves them via the index without hydrating
  the value into AL memory.

- performance/avoid-calcfields-in-loops: Add explicit exception for
  OnAfterGetRecord and OnValidate triggers, which are platform-managed
  and not developer-authored loops.

- performance/split-read-only-and-write-paths-to-avoid-locktable: Add
  ReadIsolation as the primary recommendation for read-only paths;
  LockTable reserved for confirmed write paths only.

- performance/prefer-direct-record-over-recordref: Scope the finding to
  hot unbounded loops (10k+ rows) over ledger-entry-scale tables;
  RecordRef in bounded/admin/setup contexts is not a concern.

- upgrade/enum-changes-must-be-additive-at-the-end: Replace direct
  ObsoleteState = Removed guidance with the two-stage workflow (Pending
  first, Removed later); reference use-obsolete-pending-before-removed.

- upgrade/use-datatransfer-for-large-dataset-initialization: Add the
  >300,000 records threshold as the concrete trigger for requiring
  DataTransfer.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

microsoft/knowledge/performance/avoid-calcfields-in-loops.md

@@ -17,6 +17,8 @@ CalcFields evaluates one or more FlowFields for the current record by issuing a
 
 Move CalcFields out of the iteration. If the total is what you need, use CalcSums on the filtered parent set. If row-by-row FlowField values are needed, reshape the computation so the aggregate runs once — for example by joining against a temporary table populated in a single batched query.
 
+**Acceptable exceptions:** CalcFields inside an `OnAfterGetRecord` page trigger is the standard pattern for displaying computed FlowField values — the platform calls this trigger once per row and it is not a developer-authored loop. Similarly, CalcFields inside an `OnValidate` field trigger fires at most once per user action and is acceptable. The concern is only developer-written `FindSet … repeat … until Next() = 0` loops.
+
 See sample: `avoid-calcfields-in-loops.good.al`.
 
 ## Anti Pattern

microsoft/knowledge/performance/prefer-direct-record-over-recordref.md

@@ -19,6 +19,8 @@ RecordRef and FieldRef are the platform's reflection API: they work across table
 
 Use Record variables for code paths that target a known table. Reach for RecordRef and FieldRef only when the table is genuinely dynamic (generic export/import, field-agnostic utilities, cross-table integrations).
 
+Only flag RecordRef usage as a performance concern when it appears inside a **hot, unbounded loop** — typically iterating over ledger-entry-scale tables (10,000+ rows) — where a strongly-typed Record alternative exists. RecordRef in bounded contexts, one-off operations, admin tools, setup helpers, or wizard code is not a performance concern and should not be flagged.
+
 See sample: `prefer-direct-record-over-recordref.good.al`.
 
 ## Anti Pattern

microsoft/knowledge/performance/split-read-only-and-write-paths-to-avoid-locktable.md

@@ -15,7 +15,9 @@ LockTable takes an exclusive write lock on the affected table for the remainder
 
 ## Best Practice
 
-Factor the helper so readers return immediately without a lock and only writers reach the LockTable call. A common pattern: attempt `Rec.Get()` first; if it returns the row, exit with the value; otherwise LockTable and proceed with the Insert. Document the pattern in a comment on the helper so callers understand why the LockTable is inside a branch.
+For paths that are read-only, prefer `ReadIsolation` over `LockTable`. Setting `Rec.ReadIsolation := IsolationLevel::ReadCommitted` on a record variable gives fine-grained, per-instance control over the isolation level without taking an update lock on the table for the rest of the transaction. Use `LockTable` only for paths that genuinely write to the table.
+
+For helpers that may or may not modify records, factor the code so readers return immediately without a lock and only writers reach the LockTable call. A common pattern: attempt `Rec.Get()` first; if it returns the row, exit with the value; otherwise LockTable and proceed with the Insert. Document the pattern in a comment on the helper so callers understand why the LockTable is inside a branch.
 
 See sample: `split-read-only-and-write-paths-to-avoid-locktable.good.al`.
 

microsoft/knowledge/performance/use-setloadfields-for-partial-records.md

@@ -15,7 +15,9 @@ SetLoadFields instructs the platform to hydrate only the listed fields on a reco
 
 ## Best Practice
 
-Call SetLoadFields before FindSet, FindFirst, or Get whenever the code path only reads a subset of fields. List every field that is read during the operation, including fields used in filters, calculations, and downstream function calls. Omitting a field that is later accessed triggers a second round-trip.
+Call SetLoadFields before FindSet, FindFirst, or Get whenever the code path only reads a subset of fields. List every field that is read or written during the operation, including fields used in calculations and downstream function calls. Omitting a field that is later accessed triggers a second round-trip.
+
+Fields that appear **only** in SetRange or SetFilter calls do not need to be included — the database resolves the filter using the index without hydrating the value into AL memory. Including filter-only fields wastes bandwidth and is not required.
 
 See sample: `use-setloadfields-for-partial-records.good.al`.
 

microsoft/knowledge/upgrade/enum-changes-must-be-additive-at-the-end.md

@@ -15,7 +15,14 @@ AL enums store their ordinal on disk. Inserting a new value in the middle of an
 
 ## Best Practice
 
-Append new enum values at the end, taking the next free ordinal. When a value must be retired, mark it with `ObsoleteState = Removed`, `ObsoleteReason`, and `ObsoleteTag` so tooling and downstream code can detect the deprecation; do not reclaim the ordinal. Renaming the caption on an existing ordinal is fine.
+Append new enum values at the end, taking the next free ordinal. Renaming the caption on an existing ordinal is fine.
+
+When a value must be retired, follow the two-stage obsoletion workflow:
+
+1. **First release:** Mark the value with `ObsoleteState = Pending`, `ObsoleteReason`, and `ObsoleteTag`. This gives callers at least one release cycle to migrate.
+2. **Later release:** Advance to `ObsoleteState = Removed` once all callers have been updated.
+
+Never skip straight to `ObsoleteState = Removed` without first going through `Pending` — doing so removes the warning cycle that callers depend on. Do not reclaim the ordinal in either stage. See also: `use-obsolete-pending-before-removed.md`.
 
 See sample: `enum-changes-must-be-additive-at-the-end.good.al`.
 

microsoft/knowledge/upgrade/use-datatransfer-for-large-dataset-initialization.md

@@ -15,7 +15,9 @@ An upgrade that populates a new field on millions of existing rows with a FindSe
 
 ## Best Practice
 
-Use DataTransfer for field-default initialization on existing tables, especially when the target is a ledger-entry or document-line table. Set tables, add source filters, add constant values, call CopyFields, clear, and repeat for additional slices. When trigger or subscriber behaviour is required, do that work separately against a filtered result set so the bulk update remains set-based.
+Use DataTransfer when initializing a new field on an existing table that **can contain more than 300,000 records**, or whenever a new field is added to an existing table and the initialization must run across all existing rows. Tables in the ledger-entry and document-line category reliably exceed this threshold; treat them as requiring DataTransfer by default.
+
+Set tables, add source filters, add constant values, call CopyFields, clear, and repeat for additional slices. When trigger or subscriber behaviour is required, do that work separately against a filtered result set so the bulk update remains set-based.
 
 See sample: `use-datatransfer-for-large-dataset-initialization.good.al`.