diff --git a/packages/@n8n/db/src/entities/execution-data.ts b/packages/@n8n/db/src/entities/execution-data.ts
index 9ac8251be98..a444bf07656 100644
--- a/packages/@n8n/db/src/entities/execution-data.ts
+++ b/packages/@n8n/db/src/entities/execution-data.ts
@@ -1,14 +1,15 @@
 import {
+	BeforeInsert,
+	BeforeUpdate,
 	Column,
 	Entity,
 	JoinColumn,
-	JoinTable,
 	ManyToOne,
 	OneToOne,
 	PrimaryColumn,
 	Relation,
 } from '@n8n/typeorm';
-import { IWorkflowBase } from 'n8n-workflow';
+import { IWorkflowBase, UnexpectedError } from 'n8n-workflow';
 
 import { JsonColumn } from './abstract-entity';
 import { ExecutionEntity } from './execution-entity';
@@ -16,6 +17,8 @@ import { ISimplifiedPinData } from './types-db';
 import { WorkflowHistory } from './workflow-history';
 import { idStringifier } from '../utils/transformers';
 
+type WorkflowData = Omit<IWorkflowBase, 'pinData'> & { pinData?: ISimplifiedPinData };
+
 @Entity()
 export class ExecutionData {
 	@Column('text')
@@ -31,20 +34,38 @@ export class ExecutionData {
 	 * due to `INodeExecutionData`, so we use a simplified version so `QueryDeepPartialEntity`
 	 * can resolve and calls to `update`, `insert`, and `insert` pass typechecking.
 	 */
-	@JsonColumn()
-	workflowData: Omit<IWorkflowBase, 'pinData'> & { pinData?: ISimplifiedPinData };
+	@JsonColumn({ nullable: true })
+	workflowData: WorkflowData | null;
 
 	@Column({ type: 'varchar', length: 36, nullable: true })
 	workflowVersionId: string | null;
 
 	@ManyToOne(() => WorkflowHistory, { onDelete: 'SET NULL', nullable: true })
-	@JoinTable({
-		joinColumn: {
-			name: 'workflowVersionId',
-			referencedColumnName: 'versionId',
-		},
+	@JoinColumn({
+		name: 'workflowVersionId',
+		referencedColumnName: 'versionId',
 	})
-	workflowHistory?: Relation<WorkflowHistory> | null;
+	workflowHistory: Relation<WorkflowHistory> | null;
+
+	@BeforeInsert()
+	@BeforeUpdate()
+	validateRelations() {
+		if (this.workflowData === null && this.workflowVersionId === null) {
+			throw new Error('Either workflowData or workflowVersionId must be provided');
+		}
+	}
+
+	get workflow(): WorkflowData {
+		if (this.workflowData) {
+			return this.workflowData;
+		}
+
+		if (this.workflowHistory === null) {
+			throw new UnexpectedError('ExecutionData invariant broken');
+		}
+
+		return { ...this.workflowHistory.workflow, ...this.workflowHistory };
+	}
 
 	@PrimaryColumn({ transformer: idStringifier })
 	executionId: string;
diff --git a/packages/@n8n/db/src/entities/workflow-history.ts b/packages/@n8n/db/src/entities/workflow-history.ts
index a06adadf849..0961d5bc2c9 100644
--- a/packages/@n8n/db/src/entities/workflow-history.ts
+++ b/packages/@n8n/db/src/entities/workflow-history.ts
@@ -22,7 +22,7 @@ export class WorkflowHistory extends WithTimestamps {
 	@Column()
 	authors: string;
 
-	@ManyToOne('WorkflowEntity', {
+	@ManyToOne(() => WorkflowEntity, {
 		onDelete: 'CASCADE',
 	})
 	workflow: Relation<WorkflowEntity>;
diff --git a/packages/@n8n/db/src/repositories/execution-data.repository.ts b/packages/@n8n/db/src/repositories/execution-data.repository.ts
index 44731d746c4..fdb8ddcc0ca 100644
--- a/packages/@n8n/db/src/repositories/execution-data.repository.ts
+++ b/packages/@n8n/db/src/repositories/execution-data.repository.ts
@@ -2,10 +2,11 @@ import { Service } from '@n8n/di';
 import { DataSource, In, Repository } from '@n8n/typeorm';
 import type { EntityManager } from '@n8n/typeorm';
 import type { QueryDeepPartialEntity } from '@n8n/typeorm/query-builder/QueryPartialEntity';
+import { IWorkflowBase } from 'n8n-workflow';
+
+import { ISimplifiedPinData } from 'entities/types-db';
 
 import { ExecutionData } from '../entities';
-import { IWorkflowBase } from 'n8n-workflow';
-import { ISimplifiedPinData } from 'entities/types-db';
 
 @Service()
 export class ExecutionDataRepository extends Repository<ExecutionData> {
@@ -32,10 +33,6 @@ export class ExecutionDataRepository extends Repository<ExecutionData> {
 			where: {
 				executionId: In(executionIds),
 			},
-		}).then((executionData) =>
-			executionData.map(({ workflowData, workflowHistory }) =>
-				workflowHistory ? { ...workflowHistory.workflow, ...workflowHistory } : workflowData,
-			),
-		);
+		}).then((executionData) => executionData.map(({ workflow }) => workflow));
 	}
 }
diff --git a/packages/@n8n/db/src/repositories/execution.repository.ts b/packages/@n8n/db/src/repositories/execution.repository.ts
index 1ac267aa50d..7b04771b6a2 100644
--- a/packages/@n8n/db/src/repositories/execution.repository.ts
+++ b/packages/@n8n/db/src/repositories/execution.repository.ts
@@ -330,7 +330,7 @@ export class ExecutionRepository extends Repository<ExecutionEntity> {
 			this.errorReporter.error('Found successful execution where data is empty stringified array', {
 				extra: {
 					executionId: execution.id,
-					workflowId: executionData?.workflowData.id,
+					workflowId: executionData?.workflow.id,
 				},
 			});
 		}
diff --git a/packages/cli/src/modules/chat-hub/chat-hub-message.entity.ts b/packages/cli/src/modules/chat-hub/chat-hub-message.entity.ts
index 65fb4959e2d..e6dead49008 100644
--- a/packages/cli/src/modules/chat-hub/chat-hub-message.entity.ts
+++ b/packages/cli/src/modules/chat-hub/chat-hub-message.entity.ts
@@ -127,7 +127,7 @@ export class ChatHubMessage extends WithTimestamps {
 		() => ChatHubMessage,
 		(m: ChatHubMessage) => m.previousMessage,
 	)
-	responses?: Array<Relation<ChatHubMessage>>;
+	responses?: Relation<ChatHubMessage[]>;
 
 	/**
 	 * ID of the message that this message is a retry of (if applicable).
@@ -156,7 +156,7 @@ export class ChatHubMessage extends WithTimestamps {
 		() => ChatHubMessage,
 		(m: ChatHubMessage) => m.retryOfMessage,
 	)
-	retries?: Array<Relation<ChatHubMessage>>;
+	retries?: Relation<ChatHubMessage[]>;
 
 	/**
 	 * ID of the message that this message is a revision/edit of (if applicable).
@@ -185,7 +185,7 @@ export class ChatHubMessage extends WithTimestamps {
 		() => ChatHubMessage,
 		(m: ChatHubMessage) => m.revisionOfMessage,
 	)
-	revisions?: Array<Relation<ChatHubMessage>>;
+	revisions?: Relation<ChatHubMessage[]>;
 
 	/**
 	 * Status of the message, e.g. 'running', 'success', 'error', 'cancelled'.
diff --git a/packages/cli/src/modules/chat-hub/chat-hub-session.entity.ts b/packages/cli/src/modules/chat-hub/chat-hub-session.entity.ts
index a3d12030cc2..0ecb3acb5c9 100644
--- a/packages/cli/src/modules/chat-hub/chat-hub-session.entity.ts
+++ b/packages/cli/src/modules/chat-hub/chat-hub-session.entity.ts
@@ -10,7 +10,7 @@ import {
 	PrimaryGeneratedColumn,
 } from '@n8n/typeorm';
 
-import type { ChatHubMessage } from './chat-hub-message.entity';
+import { ChatHubMessage } from './chat-hub-message.entity';
 
 @Entity({ name: 'chat_hub_sessions' })
 export class ChatHubSession extends WithTimestamps {
@@ -33,7 +33,7 @@ export class ChatHubSession extends WithTimestamps {
 	/**
 	 * The user that owns this chat session.
 	 */
-	@ManyToOne('User', { onDelete: 'CASCADE' })
+	@ManyToOne(() => User, { onDelete: 'CASCADE' })
 	@JoinColumn({ name: 'ownerId' })
 	owner?: Relation<User>;
 
@@ -53,7 +53,7 @@ export class ChatHubSession extends WithTimestamps {
 	/**
 	 * The selected credential to use by default with the selected LLM provider (if applicable).
 	 */
-	@ManyToOne('CredentialsEntity', { onDelete: 'SET NULL', nullable: true })
+	@ManyToOne(() => CredentialsEntity, { onDelete: 'SET NULL', nullable: true })
 	@JoinColumn({ name: 'credentialId' })
 	credential?: Relation<CredentialsEntity> | null;
 
@@ -78,7 +78,7 @@ export class ChatHubSession extends WithTimestamps {
 	/**
 	 * Custom n8n agent workflow to use (if applicable)
 	 */
-	@ManyToOne('WorkflowEntity', { onDelete: 'SET NULL', nullable: true })
+	@ManyToOne(() => WorkflowEntity, { onDelete: 'SET NULL', nullable: true })
 	@JoinColumn({ name: 'workflowId' })
 	workflow?: Relation<WorkflowEntity> | null;
 
@@ -100,6 +100,6 @@ export class ChatHubSession extends WithTimestamps {
 	/**
 	 * All messages that belong to this chat session.
 	 */
-	@OneToMany('ChatHubMessage', 'session')
-	messages?: Array<Relation<ChatHubMessage>>;
+	@OneToMany(() => ChatHubMessage, 'session')
+	messages?: Relation<ChatHubMessage[]>;
 }