fix(db-postgres): joins to self collection (#10182)

### What?
With Postgres, before join to self like:
```ts
import type { CollectionConfig } from 'payload'

export const SelfJoins: CollectionConfig = {
  slug: 'self-joins',
  fields: [
    {
      name: 'rel',
      type: 'relationship',
      relationTo: 'self-joins',
    },
    {
      name: 'joins',
      type: 'join',
      on: 'rel',
      collection: 'self-joins',
    },
  ],
}
```
wasn't possible, even though it's a valid usage.

### How?
Now, to differentiate parent `self_joins` and children `self_joins` we
do additional alias for the nested select -
`"4d3cf2b6_1adf_46a8_b6d2_3e1c3809d737"`:
```sql
select 
  "id", 
  "rel_id", 
  "updated_at", 
  "created_at", 
  (
    select 
      coalesce(
        json_agg(
          json_build_object('id', "joins_alias".id)
        ), 
        '[]' :: json
      ) 
    from 
      (
        select 
          "created_at", 
          "rel_id", 
          "id" 
        from 
          "self_joins" "4d3cf2b6_1adf_46a8_b6d2_3e1c3809d737" 
        where 
          "4d3cf2b6_1adf_46a8_b6d2_3e1c3809d737"."rel_id" = "self_joins"."id" 
        order by 
          "4d3cf2b6_1adf_46a8_b6d2_3e1c3809d737"."created_at" desc 
        limit 
          $1
      ) "joins_alias"
  ) as "joins_alias" 
from 
  "self_joins" 
where 
  "self_joins"."id" = $2 
order by 
  "self_joins"."created_at" desc 
limit 
  $3

```

Fixes https://github.com/payloadcms/payload/issues/10144

-->

packages/drizzle/src/find/traverseFields.ts

@@ -9,6 +9,8 @@ import type { BuildQueryJoinAliases, ChainedMethods, DrizzleAdapter } from '../t
 import type { Result } from './buildFindManyArgs.js'
 
 import buildQuery from '../queries/buildQuery.js'
+import { getTableAlias } from '../queries/getTableAlias.js'
+import { getNameFromDrizzleTable } from '../utilities/getNameFromDrizzleTable.js'
 import { jsonAggBuildObject } from '../utilities/json.js'
 import { rawConstraint } from '../utilities/rawConstraint.js'
 import { chainMethods } from './chainMethods.js'
@@ -385,12 +387,22 @@ export const traverseFields = ({
           }
         }
 
+        const columnName = `${path.replaceAll('.', '_')}${field.name}`
+
+        const subQueryAlias = `${columnName}_alias`
+
+        const { newAliasTable } = getTableAlias({
+          adapter,
+          tableName: joinCollectionTableName,
+        })
+
         const {
           orderBy,
           selectFields,
           where: subQueryWhere,
         } = buildQuery({
           adapter,
+          aliasTable: newAliasTable,
           fields,
           joins,
           locale,
@@ -418,15 +430,21 @@ export const traverseFields = ({
 
         const db = adapter.drizzle as LibSQLDatabase
 
-        const columnName = `${path.replaceAll('.', '_')}${field.name}`
+        for (let key in selectFields) {
+          const val = selectFields[key]
 
-        const subQueryAlias = `${columnName}_alias`
+          if (val.table && getNameFromDrizzleTable(val.table) === joinCollectionTableName) {
+            delete selectFields[key]
+            key = key.split('.').pop()
+            selectFields[key] = newAliasTable[key]
+          }
+        }
 
         const subQuery = chainMethods({
           methods: chainedMethods,
           query: db
             .select(selectFields as any)
-            .from(adapter.tables[joinCollectionTableName])
+            .from(newAliasTable)
             .where(subQueryWhere)
             .orderBy(() => orderBy.map(({ column, order }) => order(column))),
         }).as(subQueryAlias)
@@ -440,7 +458,7 @@ export const traverseFields = ({
               }),
             }),
           })
-          .from(sql`${subQuery}`)}`.as(columnName)
+          .from(sql`${subQuery}`)}`.as(subQueryAlias)
 
         break
       }

packages/drizzle/src/queries/buildAndOrConditions.ts

@@ -1,4 +1,4 @@
-import type { SQL } from 'drizzle-orm'
+import type { SQL, Table } from 'drizzle-orm'
 import type { FlattenedField, Where } from 'payload'
 
 import type { DrizzleAdapter, GenericColumn } from '../types.js'
@@ -8,6 +8,7 @@ import { parseParams } from './parseParams.js'
 
 export function buildAndOrConditions({
   adapter,
+  aliasTable,
   fields,
   joins,
   locale,
@@ -17,6 +18,7 @@ export function buildAndOrConditions({
   where,
 }: {
   adapter: DrizzleAdapter
+  aliasTable?: Table
   collectionSlug?: string
   fields: FlattenedField[]
   globalSlug?: string
@@ -36,6 +38,7 @@ export function buildAndOrConditions({
     if (typeof condition === 'object') {
       const result = parseParams({
         adapter,
+        aliasTable,
         fields,
         joins,
         locale,

packages/drizzle/src/queries/buildOrderBy.ts

@@ -1,3 +1,4 @@
+import type { Table } from 'drizzle-orm'
 import type { FlattenedField, Sort } from 'payload'
 
 import { asc, desc } from 'drizzle-orm'
@@ -5,10 +6,12 @@ import { asc, desc } from 'drizzle-orm'
 import type { DrizzleAdapter, GenericColumn } from '../types.js'
 import type { BuildQueryJoinAliases, BuildQueryResult } from './buildQuery.js'
 
+import { getNameFromDrizzleTable } from '../utilities/getNameFromDrizzleTable.js'
 import { getTableColumnFromPath } from './getTableColumnFromPath.js'
 
 type Args = {
   adapter: DrizzleAdapter
+  aliasTable?: Table
   fields: FlattenedField[]
   joins: BuildQueryJoinAliases
   locale?: string
@@ -22,6 +25,7 @@ type Args = {
  */
 export const buildOrderBy = ({
   adapter,
+  aliasTable,
   fields,
   joins,
   locale,
@@ -68,7 +72,10 @@ export const buildOrderBy = ({
       })
       if (sortTable?.[sortTableColumnName]) {
         orderBy.push({
-          column: sortTable[sortTableColumnName],
+          column:
+            aliasTable && tableName === getNameFromDrizzleTable(sortTable)
+              ? aliasTable[sortTableColumnName]
+              : sortTable[sortTableColumnName],
           order: sortDirection === 'asc' ? asc : desc,
         })
 

packages/drizzle/src/queries/buildQuery.ts

@@ -1,4 +1,4 @@
-import type { asc, desc, SQL } from 'drizzle-orm'
+import type { asc, desc, SQL, Table } from 'drizzle-orm'
 import type { PgTableWithColumns } from 'drizzle-orm/pg-core'
 import type { FlattenedField, Sort, Where } from 'payload'
 
@@ -15,6 +15,7 @@ export type BuildQueryJoinAliases = {
 
 type BuildQueryArgs = {
   adapter: DrizzleAdapter
+  aliasTable?: Table
   fields: FlattenedField[]
   joins?: BuildQueryJoinAliases
   locale?: string
@@ -35,6 +36,7 @@ export type BuildQueryResult = {
 }
 const buildQuery = function buildQuery({
   adapter,
+  aliasTable,
   fields,
   joins = [],
   locale,
@@ -49,6 +51,7 @@ const buildQuery = function buildQuery({
 
   const orderBy = buildOrderBy({
     adapter,
+    aliasTable,
     fields,
     joins,
     locale,
@@ -62,6 +65,7 @@ const buildQuery = function buildQuery({
   if (incomingWhere && Object.keys(incomingWhere).length > 0) {
     where = parseParams({
       adapter,
+      aliasTable,
       fields,
       joins,
       locale,

packages/drizzle/src/queries/parseParams.ts

@@ -1,4 +1,4 @@
-import type { SQL } from 'drizzle-orm'
+import type { SQL, Table } from 'drizzle-orm'
 import type { FlattenedField, Operator, Where } from 'payload'
 
 import { and, isNotNull, isNull, ne, notInArray, or, sql } from 'drizzle-orm'
@@ -9,12 +9,14 @@ import { validOperators } from 'payload/shared'
 import type { DrizzleAdapter, GenericColumn } from '../types.js'
 import type { BuildQueryJoinAliases } from './buildQuery.js'
 
+import { getNameFromDrizzleTable } from '../utilities/getNameFromDrizzleTable.js'
 import { buildAndOrConditions } from './buildAndOrConditions.js'
 import { getTableColumnFromPath } from './getTableColumnFromPath.js'
 import { sanitizeQueryValue } from './sanitizeQueryValue.js'
 
 type Args = {
   adapter: DrizzleAdapter
+  aliasTable?: Table
   fields: FlattenedField[]
   joins: BuildQueryJoinAliases
   locale: string
@@ -26,6 +28,7 @@ type Args = {
 
 export function parseParams({
   adapter,
+  aliasTable,
   fields,
   joins,
   locale,
@@ -51,6 +54,7 @@ export function parseParams({
         if (Array.isArray(condition)) {
           const builtConditions = buildAndOrConditions({
             adapter,
+            aliasTable,
             fields,
             joins,
             locale,
@@ -83,6 +87,7 @@ export function parseParams({
                   table,
                 } = getTableColumnFromPath({
                   adapter,
+                  aliasTable,
                   collectionPath: relationOrPath,
                   fields,
                   joins,
@@ -261,12 +266,18 @@ export function parseParams({
                   break
                 }
 
+                const resolvedColumn =
+                  rawColumn ||
+                  (aliasTable && tableName === getNameFromDrizzleTable(table)
+                    ? aliasTable[columnName]
+                    : table[columnName])
+
                 if (queryOperator === 'not_equals' && queryValue !== null) {
                   constraints.push(
                     or(
-                      isNull(rawColumn || table[columnName]),
+                      isNull(resolvedColumn),
                       /* eslint-disable @typescript-eslint/no-explicit-any */
-                      ne<any>(rawColumn || table[columnName], queryValue),
+                      ne<any>(resolvedColumn, queryValue),
                     ),
                   )
                   break
@@ -288,12 +299,12 @@ export function parseParams({
                 }
 
                 if (operator === 'equals' && queryValue === null) {
-                  constraints.push(isNull(rawColumn || table[columnName]))
+                  constraints.push(isNull(resolvedColumn))
                   break
                 }
 
                 if (operator === 'not_equals' && queryValue === null) {
-                  constraints.push(isNotNull(rawColumn || table[columnName]))
+                  constraints.push(isNotNull(resolvedColumn))
                   break
                 }
 
@@ -330,9 +341,7 @@ export function parseParams({
                   break
                 }
 
-                constraints.push(
+                constraints.push(adapter.operators[queryOperator](resolvedColumn, queryValue))
-                  adapter.operators[queryOperator](rawColumn || table[columnName], queryValue),
-                )
               }
             }
           }

test/joins/collections/SelfJoins.ts

@@ -0,0 +1,18 @@
+import type { CollectionConfig } from 'payload'
+
+export const SelfJoins: CollectionConfig = {
+  slug: 'self-joins',
+  fields: [
+    {
+      name: 'rel',
+      type: 'relationship',
+      relationTo: 'self-joins',
+    },
+    {
+      name: 'joins',
+      type: 'join',
+      on: 'rel',
+      collection: 'self-joins',
+    },
+  ],
+}

test/joins/config.ts

@@ -6,6 +6,7 @@ import { Categories } from './collections/Categories.js'
 import { CategoriesVersions } from './collections/CategoriesVersions.js'
 import { HiddenPosts } from './collections/HiddenPosts.js'
 import { Posts } from './collections/Posts.js'
+import { SelfJoins } from './collections/SelfJoins.js'
 import { Singular } from './collections/Singular.js'
 import { Uploads } from './collections/Uploads.js'
 import { Versions } from './collections/Versions.js'
@@ -37,6 +38,7 @@ export default buildConfigWithDefaults({
     Versions,
     CategoriesVersions,
     Singular,
+    SelfJoins,
     {
       slug: localizedPostsSlug,
       admin: {

test/joins/int.spec.ts

@@ -1,4 +1,4 @@
-import type { Payload } from 'payload'
+import type { Payload, TypeWithID } from 'payload'
 
 import path from 'path'
 import { getFileByPath } from 'payload'
@@ -975,6 +975,15 @@ describe('Joins Field', () => {
 
     await payload.delete({ collection: categoriesSlug, where: { name: { equals: 'totalDocs' } } })
   })
+
+  it('should self join', async () => {
+    const doc_1 = await payload.create({ collection: 'self-joins', data: {} })
+    const doc_2 = await payload.create({ collection: 'self-joins', data: { rel: doc_1 }, depth: 0 })
+
+    const data = await payload.findByID({ collection: 'self-joins', id: doc_1.id, depth: 1 })
+
+    expect((data.joins.docs[0] as TypeWithID).id).toBe(doc_2.id)
+  })
 })
 
 async function createPost(overrides?: Partial<Post>, locale?: Config['locale']) {

test/joins/payload-types.ts

@@ -18,6 +18,7 @@ export interface Config {
     versions: Version;
     'categories-versions': CategoriesVersion;
     singular: Singular;
+    'self-joins': SelfJoin;
     'localized-posts': LocalizedPost;
     'localized-categories': LocalizedCategory;
     'restricted-categories': RestrictedCategory;
@@ -53,6 +54,9 @@ export interface Config {
       relatedVersions: 'versions';
       relatedVersionsMany: 'versions';
     };
+    'self-joins': {
+      joins: 'self-joins';
+    };
     'localized-categories': {
       relatedPosts: 'localized-posts';
     };
@@ -71,6 +75,7 @@ export interface Config {
     versions: VersionsSelect<false> | VersionsSelect<true>;
     'categories-versions': CategoriesVersionsSelect<false> | CategoriesVersionsSelect<true>;
     singular: SingularSelect<false> | SingularSelect<true>;
+    'self-joins': SelfJoinsSelect<false> | SelfJoinsSelect<true>;
     'localized-posts': LocalizedPostsSelect<false> | LocalizedPostsSelect<true>;
     'localized-categories': LocalizedCategoriesSelect<false> | LocalizedCategoriesSelect<true>;
     'restricted-categories': RestrictedCategoriesSelect<false> | RestrictedCategoriesSelect<true>;
@@ -355,6 +360,20 @@ export interface CategoriesVersion {
   createdAt: string;
   _status?: ('draft' | 'published') | null;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "self-joins".
+ */
+export interface SelfJoin {
+  id: string;
+  rel?: (string | null) | SelfJoin;
+  joins?: {
+    docs?: (string | SelfJoin)[] | null;
+    hasNextPage?: boolean | null;
+  } | null;
+  updatedAt: string;
+  createdAt: string;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "localized-posts".
@@ -467,6 +486,10 @@ export interface PayloadLockedDocument {
         relationTo: 'singular';
         value: string | Singular;
       } | null)
+    | ({
+        relationTo: 'self-joins';
+        value: string | SelfJoin;
+      } | null)
     | ({
         relationTo: 'localized-posts';
         value: string | LocalizedPost;
@@ -666,6 +689,16 @@ export interface SingularSelect<T extends boolean = true> {
   updatedAt?: T;
   createdAt?: T;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "self-joins_select".
+ */
+export interface SelfJoinsSelect<T extends boolean = true> {
+  rel?: T;
+  joins?: T;
+  updatedAt?: T;
+  createdAt?: T;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "localized-posts_select".