---
bc-version: [all]
domain: performance
keywords: [setloadfields, partial-record, blob, bandwidth]
technologies: [al]
countries: [w1]
application-area: [all]
---

# Use SetLoadFields for partial records

## Description

SetLoadFields instructs the platform to hydrate only the listed fields on a record variable. On wide tables, or tables with BLOB or media fields, the difference is substantial: a Sales Invoice Line has dozens of fields and loading all of them for every row of a large set is wasted bandwidth. Primary key fields, SystemId, and system audit fields are always loaded automatically. SetLoadFields works only with FieldClass = Normal; FlowFields and FlowFilters cannot be partial-loaded.

## Best Practice

Call SetLoadFields before FindSet, FindFirst, or Get when the table is wide enough to matter (roughly 10+ fields) and the code path reads a small subset (roughly under 60%) across a material number of rows. Short loops over narrow tables usually do not earn the extra coupling; see `skip-setloadfields-on-narrow-tables-and-short-loops` for that exception. 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`.

## Anti Pattern

Iterating a large set and reading only two or three fields without SetLoadFields forces the platform to transport every column for every row, including BLOBs and unused text fields.

See sample: `use-setloadfields-for-partial-records.bad.al`.