---
bc-version: [26..28]
domain: performance
keywords: [report, addloadfields, ondatapreitem, layout, partial-record]
technologies: [al]
countries: [w1]
application-area: [all]
---

# Use AddLoadFields in report dataitems

> **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

Reports iterate a dataitem's record automatically; the developer does not control the Find call directly. AddLoadFields, called in OnPreDataItem, tells the platform which fields the layout and the dataitem triggers will read. Without it the report streams every field of every row — for a ledger-entry dataitem on a production tenant, that is the dominant cost of the report.

## Best Practice

In each dataitem's OnPreDataItem trigger, call AddLoadFields for every field used by the layout, by the dataitem's triggers, and by any code that runs in the row-level event hooks. If the layout uses a FlowField, also ensure CalcFields is called and that the underlying key is loaded (see add-sift-keys-for-flowfields).

See sample: `use-addloadfields-in-report-layouts.good.al`.

## Anti Pattern

Omitting AddLoadFields is the default for reports generated by the AL wizard. For a dataitem backed by a ledger-entry table, this silently turns the report into a full-column scan.