Query email to last createdAt for given event type

backend/src/graphql/resolver/util/eventList.ts

@@ -0,0 +1,16 @@
+import { Event as DbEvent } from '@entity/Event'
+import { User } from '@entity/User'
+import { UserContact } from '@entity/UserContact'
+
+export const lastDateTimeEvents = async (eventType: string): Promise<DbEvent[]> => {
+  return DbEvent
+    .createQueryBuilder('event')
+    .select('MAX(event.created_at)', 'value')
+    .leftJoin(User, 'user', 'affected_user_id = user.id')
+    .leftJoin(UserContact, 'usercontact', 'user.id = usercontact.user_id')
+    .addSelect('usercontact.email', 'email')
+    .where('event.type = :eventType', { eventType })
+    .andWhere('usercontact.email IS NOT NULL')
+    .groupBy('event.affected_user_id')
+    .getRawMany()
+}