diff --git a/server/models/NotificationSetting.js b/server/models/NotificationSetting.js
index 69971d64..6e5be653 100644
--- a/server/models/NotificationSetting.js
+++ b/server/models/NotificationSetting.js
@@ -52,6 +52,7 @@ NotificationSetting.associate = models => {
   NotificationSetting.belongsTo(models.User, {
     as: 'user',
     foreignKey: 'userId',
+    onDelete: 'cascade',
   });
   NotificationSetting.belongsTo(models.Team, {
     as: 'team',
diff --git a/server/models/Revision.js b/server/models/Revision.js
index c138cfec..fafcc61a 100644
--- a/server/models/Revision.js
+++ b/server/models/Revision.js
@@ -9,29 +9,13 @@ const Revision = sequelize.define('revision', {
   },
   title: DataTypes.STRING,
   text: DataTypes.TEXT,
-
-  userId: {
-    type: 'UUID',
-    allowNull: false,
-    references: {
-      model: 'users',
-    },
-  },
-
-  documentId: {
-    type: 'UUID',
-    allowNull: false,
-    references: {
-      model: 'documents',
-      onDelete: 'CASCADE',
-    },
-  },
 });
 
 Revision.associate = models => {
   Revision.belongsTo(models.Document, {
     as: 'document',
     foreignKey: 'documentId',
+    onDelete: 'cascade',
   });
   Revision.belongsTo(models.User, {
     as: 'user',
diff --git a/server/models/User.js b/server/models/User.js
index d1f7acad..24231310 100644
--- a/server/models/User.js
+++ b/server/models/User.js
@@ -39,17 +39,16 @@ const User = sequelize.define(
         return !!this.suspendedAt;
       },
     },
-    indexes: [
-      {
-        fields: ['email'],
-      },
-    ],
   }
 );
 
 // Class methods
 User.associate = models => {
-  User.hasMany(models.ApiKey, { as: 'apiKeys' });
+  User.hasMany(models.ApiKey, { as: 'apiKeys', onDelete: 'cascade' });
+  User.hasMany(models.NotificationSetting, {
+    as: 'notificationSettings',
+    onDelete: 'cascade',
+  });
   User.hasMany(models.Document, { as: 'documents' });
   User.hasMany(models.View, { as: 'views' });
 };
@@ -93,9 +92,19 @@ const setRandomJwtSecret = model => {
   model.jwtSecret = crypto.randomBytes(64).toString('hex');
 };
 
-const removeIdentifyingInfo = async model => {
-  await ApiKey.destroy({ where: { userId: model.id } });
-  await Star.destroy({ where: { userId: model.id } });
+const removeIdentifyingInfo = async (model, options) => {
+  await NotificationSetting.destroy({
+    where: { userId: model.id },
+    transaction: options.transaction,
+  });
+  await ApiKey.destroy({
+    where: { userId: model.id },
+    transaction: options.transaction,
+  });
+  await Star.destroy({
+    where: { userId: model.id },
+    transaction: options.transaction,
+  });
 
   model.email = '';
   model.name = 'Unknown';
@@ -108,7 +117,7 @@ const removeIdentifyingInfo = async model => {
 
   // this shouldn't be needed once this issue is resolved:
   // https://github.com/sequelize/sequelize/issues/9318
-  await model.save({ hooks: false });
+  await model.save({ hooks: false, transaction: options.transaction });
 };
 
 const checkLastAdmin = async model => {