diff --git a/backend/src/entities/assigments/submission.entity.ts b/backend/src/entities/assigments/submission.entity.ts
index 57f7f980..8f833518 100644
--- a/backend/src/entities/assigments/submission.entity.ts
+++ b/backend/src/entities/assigments/submission.entity.ts
@@ -5,9 +5,6 @@ import {Language} from "../content/language";
 
 @Entity()
 export class Submission<T> {
-    @ManyToOne({entity: () => Student, primary: true})
-    submitter!: Student;
-
     @PrimaryKey({type: "string"})
     learningObjectHruid!: string;
 
@@ -15,10 +12,16 @@ export class Submission<T> {
     learningObjectLanguage!: Language;
 
     @PrimaryKey({type: "string"})
-    learningObjectVersion: number = "1";
+    learningObjectVersion: string = "1";
 
-    @PrimaryKey({type: "datetime"})
-    submissionTime: Date;
+    @Property({type: "integer"})
+    submissionNumber!: number;
+
+    @ManyToOne({entity: () => Student})
+    submitter!: Student;
+
+    @Property({type: "datetime"})
+    submissionTime!: Date;
 
     @ManyToOne({entity: () => Group, nullable: true})
     onBehalfOf?: Group;
diff --git a/backend/src/entities/questions/answer.entity.ts b/backend/src/entities/questions/answer.entity.ts
index 545482a8..6dac636f 100644
--- a/backend/src/entities/questions/answer.entity.ts
+++ b/backend/src/entities/questions/answer.entity.ts
@@ -11,9 +11,12 @@ export class Answer {
     @ManyToOne({entity: () => Question, primary: true})
     toQuestion!: Question;
 
-    @PrimaryKey({type: "datetime"})
-    timestamp: Date;
+    @PrimaryKey({type: "integer"})
+    sequenceNumber!: number;
+
+    @Property({type: "datetime"})
+    timestamp!: Date;
 
     @Property({type: "text"})
-    content: string;
+    content!: string;
 }
diff --git a/backend/src/entities/questions/question.entity.ts b/backend/src/entities/questions/question.entity.ts
index 3a2976c5..34aa4bb2 100644
--- a/backend/src/entities/questions/question.entity.ts
+++ b/backend/src/entities/questions/question.entity.ts
@@ -4,9 +4,6 @@ import {Student} from "../users/student.entity";
 
 @Entity()
 export class Question {
-    @ManyToOne({entity: () => Student, primary: true})
-    author!: Student;
-
     @PrimaryKey({type: "string"})
     learningObjectHruid!: string;
 
@@ -14,9 +11,15 @@ export class Question {
     learningObjectLanguage!: Language;
 
     @PrimaryKey({type: "string"})
-    learningObjectVersion!: number = "1";
+    learningObjectVersion: string = "1";
 
-    @PrimaryKey({type: "datetime"})
+    @PrimaryKey({type: "integer"})
+    sequenceNumber!: number;
+
+    @ManyToOne({entity: () => Student})
+    author!: Student;
+
+    @Property({type: "datetime"})
     timestamp!: Date;
 
     @Property({type: "text"})