bcquality/microsoft/knowledge/performance/dataaccessintent-readonly-on-analytical-objects.md
Jesper Schulz-Wedde 42ff075793 Promote knowledge for Microsoft review skills
Move canonical knowledge for Microsoft-owned review domains into the Microsoft layer and document the skill/knowledge co-location policy.

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

Copilot-Session: 2a6ea875-d38e-4f30-aadb-0d606f9be231
2026-09-03 14:59:44 +02:00

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---
bc-version: ["16.."]
domain: performance
keywords: [dataaccessintent, read-only, read-scale-out, report, api-page, query]
technologies: [al]
countries: [w1]
application-area: [all]
---
# Set DataAccessIntent ReadOnly on analytical objects
> Contributions welcome — open a PR to refine or extend this article.
## Description
`DataAccessIntent` was introduced at runtime 5.0 (BC 16) and has no effect in earlier versions. Reports, API pages (`PageType = API` with `Editable = false`), and queries that only read can run against a read replica when `DataAccessIntent = ReadOnly`. For queries, replica routing only applies when the query is exposed via OData/API; running a query in AL code is unaffected. Without the property these objects hit the primary replica and compete with posting. Agents omit it because the default is read-write and the object "only reads" in AL. The replica routing is a metadata switch, not something the compiler infers from the absence of `Modify`.
## Best Practice
On report objects and `PageType = API` pages with `Editable = false` that never write, set `DataAccessIntent = ReadOnly`. For query objects, set it when the query is consumed via OData or an API endpoint. Keep the default on objects that insert, modify, or call a write codeunit from a processing-only report.
See sample: `dataaccessintent-readonly-on-analytical-objects.good.al`.
## Anti Pattern
A listing report or API query with no `DataAccessIntent` that scans G/L or sales lines. The object is read-only in practice and still loads the primary.
See sample: `dataaccessintent-readonly-on-analytical-objects.bad.al`.