vault backup: 2026-05-15 16:34:07

wiki/_master-index.md

@@ -35,7 +35,7 @@ This 3-hop pattern works for hundreds of articles without vector search.
 | [[wiki/reports/_index\|reports/]] | Weekly and monthly summaries — generate: `uv run python scripts/report-generator.py --weekly` | 1 |
 | [[wiki/infrastructure/_index\|infrastructure/]] | Server inventory: all 10 SSH hosts — optical, optical-dev, optical-prod, baic, librechat, modocmms, box-cli, aimpress, pve | 12 |
 | [[wiki/testing/_index\|testing/]] | Web app testing: functional, performance, security, UI types; TDD/BDD/Agile methodologies; Selenium/Cypress/Playwright/JMeter/OWASP ZAP tools | 1 |
-| [[wiki/payloadcms/_index\|payloadcms/]] | Full Payload CMS reference — getting started, config, database (Postgres/MongoDB/SQLite), all 22 field types, access control, hooks, authentication (cookies, JWT, API keys, custom strategies, token data), admin UI, custom components, Lexical rich text, live preview, versions/drafts, Local/REST/GraphQL APIs, queries, plugins, jobs queue, upload, ecommerce, production deploy, TypeScript, migration guides, i18n, localization, hierarchy | 127 |
+| [[wiki/payloadcms/_index\|payloadcms/]] | Full Payload CMS reference — getting started, config, database (Postgres/MongoDB/SQLite), all 22 field types, access control, hooks, authentication (cookies, JWT, API keys, custom strategies, token data), admin UI, custom components, Lexical rich text, live preview, versions/drafts, Local/REST/GraphQL APIs, queries, plugins, jobs queue, upload, ecommerce, production deploy, TypeScript, migration guides, i18n, localization, hierarchy | 128 |
 
 | [[wiki/shared-patterns/_index\|shared-patterns/]] | Oliver Agency standard library patterns: httpx, structlog, pydantic-settings, alembic — reuse before writing from scratch | 4 |
 | [[wiki/mistakes/_index\|mistakes/]] | Anti-patterns extracted from sessions — per-stack running lists (fastapi, react, docker, postgres, general) — injected at session start | 5 |

wiki/payloadcms/_index.md

@@ -128,3 +128,4 @@
 | [[wiki/payloadcms/production-preventing-abuse\|Production — Preventing API Abuse]] | Login rate limiting (maxLoginAttempts/lockTime), maxDepth, CSRF, CORS, GraphQL complexity limits, malicious file upload mitigation | raw/production__preventing-abuse.md | 2026-05-15 |
 | [[wiki/payloadcms/queries-depth\|Queries — Depth (Relationship Population)]] | depth=0 (IDs only) vs depth=N (full objects), defaultDepth config, field-level maxDepth cap, performance notes, GraphQL exception | raw/queries__depth.md | 2026-05-15 |
 | [[wiki/payloadcms/queries-pagination\|Queries — Pagination]] | Default pagination (limit/page/pagination options), response shape (docs + metadata), limit:1 perf tip, disabling pagination for bulk ops | raw/queries__pagination.md | 2026-05-15 |
+| [[wiki/payloadcms/queries-select\|Queries — Select & Populate]] | Include/exclude field selection at DB level, entity-level `select` function for hooks/access, `defaultPopulate` for relationship optimization, `populate` override | raw/queries__select.md | 2026-05-15 |

wiki/payloadcms/queries-select.md

@@ -0,0 +1,161 @@
+---
+title: "Queries — Select & Populate"
+aliases: [payload-select, payload-populate, payload-defaultPopulate]
+tags: [payloadcms, queries, performance, select, populate]
+sources: [raw/queries__select.md]
+created: 2026-05-15
+updated: 2026-05-15
+---
+
+## Overview
+
+By default Payload returns **all fields** for every query. The Select API lets you specify exactly which fields to return, reducing DB load and response size.
+
+---
+
+## Include / Exclude Modes
+
+`select` operates in one of two modes depending on the values you pass:
+
+| Mode | How | Result |
+|------|-----|--------|
+| **Include** | Set fields to `true` | Only those fields + `id` |
+| **Exclude** | Set fields to `false` | All fields except those |
+
+```ts
+// Include mode — only id, text, group.number, array
+await payload.find({
+  collection: 'posts',
+  select: {
+    text: true,
+    group: { number: true },
+    array: true,
+  },
+})
+
+// Exclude mode — all fields except array and group.number
+await payload.find({
+  collection: 'posts',
+  select: {
+    array: false,
+    group: { number: false },
+  },
+})
+```
+
+### Empty select
+
+Always returns **only `id`** — the `id` field is always included regardless of your `select`.
+
+```ts
+const post = await payload.findByID({ collection: 'posts', id: '1', select: {} })
+// → { id: '1' }
+```
+
+---
+
+## Entity-Level `select` Config
+
+Both Collections and Globals accept a top-level `select` function that runs **before every read**. Use it to force fields into every query regardless of what the caller requests.
+
+```ts
+export const Posts: CollectionConfig = {
+  slug: 'posts',
+  // Always include `title` — required by access control / hooks
+  select: ({ select }) => (select ? { ...select, title: true } : undefined),
+  fields: [ /* ... */ ],
+}
+```
+
+- Receives `{ operation, req, select }` → returns the final `select` to apply
+- **Replaces** (not merges) the caller's select — spread `select` when you want to add
+- Return `undefined` to leave the caller's select untouched
+- Per-document data is **not** available (runs before the read)
+
+> **Warning:** `beforeRead` and `afterRead` hooks may not receive the full `doc` when `select` is active. Use entity-level config to guarantee field availability in hooks/access control.
+
+---
+
+## REST API
+
+Use bracket notation in query params; prefer `qs-esm` for complex queries:
+
+```ts
+// Direct
+fetch('https://localhost:3000/api/posts?select[color]=true&select[group][number]=true')
+
+// With qs-esm (recommended)
+import { stringify } from 'qs-esm'
+
+const stringifiedQuery = stringify({ select: { text: true, group: { number: true } } }, { addQueryPrefix: true })
+const response = await fetch(`http://localhost:3000/api/posts${stringifiedQuery}`)
+```
+
+Same syntax works for Globals via `/api/globals/<slug>`.
+
+---
+
+## `defaultPopulate` — Optimize Relationship Population
+
+Set on a Collection to control which fields are returned when that collection is **populated** (via Relationship or Upload fields in other documents).
+
+```ts
+export const Pages: CollectionConfig<'pages'> = {
+  slug: 'pages',
+  defaultPopulate: {
+    slug: true,   // only return slug when populated from another doc
+  },
+  fields: [{ name: 'slug', type: 'text', required: true }],
+}
+```
+
+> **Warning (Upload fields):** If you include `url` in `defaultPopulate`, you **must** also include `filename: true`, otherwise Payload cannot construct the file URL and returns `url: null`.
+
+---
+
+## `populate` Override
+
+Override `defaultPopulate` per-query via the `populate` option:
+
+```ts
+// Local API
+await payload.find({
+  collection: 'posts',
+  populate: {
+    pages: { text: true },  // overrides defaultPopulate on Pages collection
+  },
+})
+
+// REST API
+fetch('https://localhost:3000/api/posts?populate[pages][text]=true')
+```
+
+---
+
+## Key Takeaways
+
+- `select` is applied at the **database level** — efficient but means hooks may receive partial docs
+- Use **entity-level `select` function** to guarantee fields in hooks/access control
+- `id` is always returned — even with `select: {}`
+- `defaultPopulate` on a Collection drastically reduces JSON from relationship fields — set it for any collection only needed as a reference (e.g. pages linked by slug)
+- For Upload collections: `defaultPopulate` with `url` requires `filename: true` alongside it
+- Use `qs-esm` for REST API select/populate — raw bracket notation gets unwieldy fast
+
+---
+
+## Related
+
+- [[wiki/payloadcms/queries|Queries — Full Reference]]
+- [[wiki/payloadcms/queries-depth|Queries — Depth (Relationship Population)]]
+- [[wiki/payloadcms/queries-pagination|Queries — Pagination]]
+- [[wiki/payloadcms/fields-relationship|Relationship Field]]
+- [[wiki/payloadcms/fields-upload|Upload Field]]
+- [[wiki/payloadcms/hooks|Hooks Overview]]
+- [[wiki/payloadcms/local-api|Local API]]
+- [[wiki/payloadcms/rest-api|REST API]]
+
+---
+
+## Sources
+
+- `raw/queries__select.md` — https://payloadcms.com/docs/queries/select