feat: change unique idx on messsaging table (#17636)

* change unique idx on messsaging table

* not atomic

latest_migrations.manifest

@@ -5,7 +5,7 @@ contenttypes: 0002_remove_content_type_name
 ee: 0015_add_verified_properties
 otp_static: 0002_throttling
 otp_totp: 0002_auto_20190420_0723
-posthog: 0351_team_surveys_opt_in
+posthog: 0352_auto_20230926_1833
 sessions: 0001_initial
 social_django: 0010_uid_db_index
 two_factor: 0007_auto_20201201_1019

posthog/migrations/0352_auto_20230926_1833.py

@@ -0,0 +1,28 @@
+# Generated by Django 3.2.19 on 2023-09-26 18:33
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    atomic = False  # Cannot create index concurrently atomically
+
+    dependencies = [
+        ("posthog", "0351_team_surveys_opt_in"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="messagingrecord",
+            name="campaign_count",
+            field=models.IntegerField(null=True),
+        ),
+        migrations.RunSQL(
+            sql="""
+            CREATE UNIQUE INDEX CONCURRENTLY idx_messagingrecord_unique_on_email_hash_campaign_key_campaign_count
+            ON posthog_messagingrecord (email_hash, campaign_key, campaign_count);
+            """,
+            reverse_sql="""
+            DROP INDEX CONCURRENTLY "idx_messagingrecord_unique_on_email_hash_campaign_key_campaign_count";
+            """,
+        ),
+    ]

posthog/models/messaging.py

@@ -21,11 +21,12 @@ def get_or_create(self, defaults=None, **kwargs):
 
 
 class MessagingRecord(UUIDModel):
-
     objects = MessagingRecordManager()
 
     email_hash: models.CharField = models.CharField(max_length=1024)
     campaign_key: models.CharField = models.CharField(max_length=128)
+    # Numeric indicator for repeat emails of the same campaign key
+    campaign_count: models.IntegerField = models.IntegerField(null=True)
     sent_at: models.DateTimeField = models.DateTimeField(null=True)
     created_at: models.DateTimeField = models.DateTimeField(auto_now_add=True)