Miranda Limonczenko d2ccbe5d46 docs(database): close the RLS guide gaps the eval flagged (#49011) ...

Closes DOCS-1274

## Problem

The `build-docs-002-rls-guide` eval points an agent at the Row Level
Security guide with a vibe-coder prompt that never says RLS, policy,
role, or test. It failed 6 of 35 checks. Each failure traces to
something the guide doesn't say.

- **Grants.** `anon` kept insert, update, and delete on all four to-do
tables. Both client roles kept writes on the weather feed. 24 privileges
untouched.
- **Indexes.** Missing on `list_members.user_id`. The agent indexed the
other three, so it missed the composite-primary-key case specifically.
- **Tests.** No pgTAP files. `Result: NOTESTS`, so the coverage judge
never ran.

## Solution

- **Add a `Grants and policies` section.**
- **Rewrite the opening danger admonition around revoke-then-grant.** It
previously showed `grant` only, which reads as though privileges start
from nothing.
- **Drop the `(or primary keys)` carve-out from `Add indexes`.** A
column counts as indexed only when it leads a `btree` index, shown with
a composite-primary-key example.
- **Add a `Test your policies` section.** Covers file location under
`supabase/tests/`, `supabase test db`, role and identity switching,
which assertion matches which denial, and an 11-assertion example
spanning allow and deny for all four operations across `anon` and
`authenticated`.

Used the supacademy RLS course as a second reference. Its framing of
grants running before RLS shaped the new section.

## Manual testing

1. Open the [Row Level Security
guide](https://docs-git-docs-rls-revision-supabase.vercel.app/docs/guides/database/postgres/row-level-security)
on the preview. `Grants and policies` and `Test your policies` appear in
the table of contents.
2. Select the `Grants and policies` link at the end of the first
admonition. It jumps to the new section.
3. Open the [markdown
version](https://docs-git-docs-rls-revision-supabase.vercel.app/docs/guides/database/postgres/row-level-security.md),
which is what agents fetch. Both new sections and the revised `Add
indexes` text are present.
4. From `apps/docs`, run `pnpm lint:mdx`. The 4 warnings on this file
match `master`, with no new ones.



<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

## Documentation

* Clarified that exposed tables must enable row-level security.
* Explained the distinction between database grants and row-level
security policies.
* Added least-privilege examples for client roles, including read-only
access.
* Added pgTAP testing guidance with a complete `profiles` example.
* Clarified that composite indexes support policy filters only on their
leading columns.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

2026-08-17 15:05:39 -07:00

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troubleshooting

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navigation.references.ts

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