fix(drizzle): skip foreign key for blocks that are shared across collections

packages/drizzle/src/schema/build.ts

@@ -1,4 +1,4 @@
-import type { FlattenedField, SanitizedCompoundIndex } from 'payload'
+import type { Block, FlattenedField, SanitizedCompoundIndex } from 'payload'
 
 import { InvalidConfiguration } from 'payload'
 import toSnakeCase from 'to-snake-case'
@@ -48,6 +48,7 @@ type Args = {
   rootTableName?: string
   rootUniqueRelationships?: Set<string>
   setColumnID: SetColumnID
+  sharedBlocks?: Set<Block>
   tableName: string
   timestamps?: boolean
   versions: boolean
@@ -85,6 +86,7 @@ export const buildTable = ({
   rootTableName: incomingRootTableName,
   rootUniqueRelationships,
   setColumnID,
+  sharedBlocks,
   tableName,
   timestamps,
   versions,
@@ -141,6 +143,7 @@ export const buildTable = ({
     rootTableIDColType: rootTableIDColType || idColType,
     rootTableName,
     setColumnID,
+    sharedBlocks,
     uniqueRelationships,
     versions,
     withinLocalizedArrayOrBlock,

packages/drizzle/src/schema/buildRawSchema.ts

@@ -9,6 +9,7 @@ import type { DrizzleAdapter, RawIndex, SetColumnID } from '../types.js'
 
 import { createTableName } from '../createTableName.js'
 import { buildIndexName } from '../utilities/buildIndexName.js'
+import { findSharedBlocks } from '../utilities/findSharedBlocks.js'
 import { buildTable } from './build.js'
 
 /**
@@ -24,6 +25,8 @@ export const buildRawSchema = ({
   adapter.indexes = new Set()
   adapter.foreignKeys = new Set()
 
+  const sharedBlocks = findSharedBlocks(adapter.payload);
+
   adapter.payload.config.collections.forEach((collection) => {
     createTableName({
       adapter,
@@ -65,6 +68,7 @@ export const buildRawSchema = ({
       fields: collection.flattenedFields,
       parentIsLocalized: false,
       setColumnID,
+      sharedBlocks,
       tableName,
       timestamps: collection.timestamps,
       versions: false,
@@ -85,6 +89,7 @@ export const buildRawSchema = ({
         fields: versionFields,
         parentIsLocalized: false,
         setColumnID,
+        sharedBlocks,
         tableName: versionsTableName,
         timestamps: true,
         versions: true,
@@ -106,6 +111,7 @@ export const buildRawSchema = ({
       fields: global.flattenedFields,
       parentIsLocalized: false,
       setColumnID,
+      sharedBlocks,
       tableName,
       timestamps: false,
       versions: false,
@@ -129,6 +135,7 @@ export const buildRawSchema = ({
         fields: versionFields,
         parentIsLocalized: false,
         setColumnID,
+        sharedBlocks,
         tableName: versionsTableName,
         timestamps: true,
         versions: true,

packages/drizzle/src/schema/traverseFields.ts

@@ -1,4 +1,4 @@
-import type { FlattenedField } from 'payload'
+import type { Block, FlattenedField } from 'payload'
 
 import { InvalidConfiguration } from 'payload'
 import {
@@ -56,6 +56,7 @@ type Args = {
   rootTableIDColType: IDType
   rootTableName: string
   setColumnID: SetColumnID
+  sharedBlocks?: Set<Block>
   uniqueRelationships: Set<string>
   versions: boolean
   /**
@@ -97,6 +98,7 @@ export const traverseFields = ({
   rootTableIDColType,
   rootTableName,
   setColumnID,
+  sharedBlocks,
   uniqueRelationships,
   versions,
   withinLocalizedArrayOrBlock,
@@ -450,8 +452,13 @@ export const traverseFields = ({
               },
             }
 
-            const baseForeignKeys: Record<string, RawForeignKey> = {
-              _parentIdFk: {
+            const isSharedBlock = sharedBlocks && sharedBlocks.has(block.originalRef)
+            const baseForeignKeys: Record<string, RawForeignKey> = {}
+
+            const skipForeignKey = isSharedBlock && block.dbName
+
+            if (!skipForeignKey) {
+              baseForeignKeys._parentIdFk = {
                 name: `${blockTableName}_parent_id_fk`,
                 columns: ['_parentID'],
                 foreignColumns: [
@@ -461,7 +468,7 @@ export const traverseFields = ({
                   },
                 ],
                 onDelete: 'cascade',
-              },
+              }
             }
 
             const isLocalized =

packages/drizzle/src/utilities/findSharedBlocks.spec.ts

@@ -0,0 +1,62 @@
+import { Block, Payload, sanitizeConfig } from 'payload'
+import { findSharedBlocks } from './findSharedBlocks'
+const block_1: Block = {
+  slug: 'test-block',
+  fields: [],
+}
+
+const block_2: Block = {
+  slug: 'test-block-non-shared',
+  fields: [],
+}
+
+const getPayload = async () => {
+  return {
+    config: await sanitizeConfig({
+      collections: [
+        {
+          slug: 'collection-1',
+          fields: [
+            {
+              type: 'blocks',
+              name: 'blocks',
+              blocks: [block_1],
+            },
+          ],
+        },
+        {
+          slug: 'collection-2',
+          fields: [
+            {
+              type: 'group',
+              name: 'group',
+              fields: [
+                {
+                  type: 'blocks',
+                  name: 'blocks',
+                  blocks: [block_1, block_2],
+                },
+              ],
+            },
+          ],
+        },
+      ],
+    } as any),
+  } as Payload
+}
+
+describe('findSharedBlocks', () => {
+  it('should find block_1 as shared', async () => {
+    const payload = await getPayload()
+    const map = findSharedBlocks(payload)
+    expect(map.size).toBe(1)
+    expect(map.has(block_1)).toBe(true)
+  })
+
+  it('should not find block_2 as shared', async () => {
+    const payload = await getPayload()
+    const map = findSharedBlocks(payload)
+    expect(map.size).toBe(1)
+    expect(map.has(block_2)).toBe(false)
+  })
+})

packages/drizzle/src/utilities/findSharedBlocks.ts

@@ -0,0 +1,63 @@
+import type { Block, Field, FlattenedField, Payload } from 'payload'
+
+/**
+ * Helper function to find all shared blocks across collections and globals.
+ * A block is considered "shared" if the same JS reference appears in multiple collections/globals.
+ *
+ * @param payload - The Payload instance
+ * @returns A Set of block references that are shared across multiple collections/globals
+ */
+export const findSharedBlocks = (payload: Payload): Set<Block> => {
+  const blockReferencesMap = new Map<Block, Set<string>>() // Map<blockReference, Set<collectionSlug>>
+
+  /**
+   * Recursively traverse fields to find block usage
+   * @param fields - Array of field configurations
+   * @param parentSlug - The slug of the parent collection/global
+   */
+  const traverseFieldsForBlocks = (fields: FlattenedField[], parentSlug: string): void => {
+    fields.forEach((field) => {
+      if (field.type === 'blocks') {
+        const blockRefs = field.blockReferences ?? field.blocks
+        if (blockRefs) {
+          blockRefs.forEach((blockRef) => {
+            const block = typeof blockRef === 'string' ? payload.blocks[blockRef] : blockRef
+
+            if (!blockReferencesMap.has(block.originalRef)) {
+              blockReferencesMap.set(block.originalRef, new Set<string>())
+            }
+            const blockSet = blockReferencesMap.get(block.originalRef)
+            if (blockSet) {
+              blockSet.add(parentSlug)
+            }
+          })
+        }
+      }
+
+      // Recursively check nested fields
+      if ('flattenedFields' in field) {
+        traverseFieldsForBlocks(field.flattenedFields, parentSlug)
+      }
+    })
+  }
+
+  // Check all collections
+  payload.config.collections.forEach((collection) => {
+    traverseFieldsForBlocks(collection.flattenedFields, collection.slug)
+  })
+
+  // Check all globals
+  payload.config.globals.forEach((global) => {
+    traverseFieldsForBlocks(global.flattenedFields, global.slug)
+  })
+
+  // Return only blocks that are used in multiple collections/globals
+  const sharedBlocks = new Set<Block>()
+  blockReferencesMap.forEach((collections, blockRef) => {
+    if (collections.size > 1) {
+      sharedBlocks.add(blockRef)
+    }
+  })
+
+  return sharedBlocks
+}

packages/payload/src/fields/config/types.ts

@@ -1713,6 +1713,7 @@ export type JoinFieldClient = {
 
 export type FlattenedBlock = {
   flattenedFields: FlattenedField[]
+  originalRef?: Block
 } & Block
 
 export type FlattenedBlocksField = {

packages/payload/src/utilities/flattenAllFields.ts

@@ -13,6 +13,7 @@ export const flattenBlock = ({ block }: { block: Block }): FlattenedBlock => {
   return {
     ...block,
     flattenedFields: flattenAllFields({ fields: block.fields }),
+    originalRef: block,
   }
 }