bcquality/microsoft/knowledge/performance/skip-setloadfields-on-write-and-transferfields.md

bc-version	domain	keywords	technologies	countries	application-area
all	performance	setloadfields partial-record jit-load modify insert transferfields write-path	al	w1	all

Skip SetLoadFields on write and copy paths

Contributions welcome — open a PR to refine or extend this article.

Description

SetLoadFields is a read optimization. The platform's partial-record usage guidelines list the operations that require every field to already be present: Insert, Delete, Rename, TransferFields, and copying a record into a temporary table. When those operations run on a partial record, the platform issues a just-in-time load of the missing fields. That extra round-trip costs more than loading the full row on the original FindSet or Get. Note: Modify itself is not in this list — a Modify(false) that only touches loaded fields is safe with a partial record.

Best Practice

Omit SetLoadFields on loops whose body performs a documented full-load operation (Insert, Delete, Rename, TransferFields, or assignment into a temporary record) on the same record variable, so the initial read already materializes every field those operations need.

See sample: skip-setloadfields-on-write-and-transferfields.good.al.

Anti Pattern

Calling SetLoadFields immediately before a FindSet whose body performs Delete, Rename, TransferFields, or copies the record into a temporary table. The review signal is a partial-record setup on a record variable that feeds one of these documented full-load operations in the same iteration.

See sample: skip-setloadfields-on-write-and-transferfields.bad.al.