From 959b17f74cd4d5713ff629ed79ce5d8752ca038f Mon Sep 17 00:00:00 2001
From: Sandy Spicer <sandy@posthog.com>
Date: Wed, 11 Sep 2024 08:52:20 -0700
Subject: [PATCH] fix: retention query returns wrong results with
 target_first_time (#24901)

---
 .../insights/retention_query_runner.py        |  7 ++-
 .../test/test_retention_query_runner.py       | 58 +++++++++++++++++++
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/posthog/hogql_queries/insights/retention_query_runner.py b/posthog/hogql_queries/insights/retention_query_runner.py
index f5d817e2eb7f8..9bbb21e109a19 100644
--- a/posthog/hogql_queries/insights/retention_query_runner.py
+++ b/posthog/hogql_queries/insights/retention_query_runner.py
@@ -170,7 +170,12 @@ def actor_query(self, breakdown_values_filter: Optional[int] = None) -> ast.Sele
                 {
                     "target_timestamps": target_timestamps,
                     "min_timestamp": self.query_date_range.date_to_start_of_interval_hogql(
-                        parse_expr("min(events.timestamp)")
+                        parse_expr(
+                            "minIf(events.timestamp, {target_entity_expr})",
+                            {
+                                "target_entity_expr": target_entity_expr,
+                            },
+                        )
                     ),
                 },
             )
diff --git a/posthog/hogql_queries/insights/test/test_retention_query_runner.py b/posthog/hogql_queries/insights/test/test_retention_query_runner.py
index 7e096d7a9ab64..bc97e8b7d51d3 100644
--- a/posthog/hogql_queries/insights/test/test_retention_query_runner.py
+++ b/posthog/hogql_queries/insights/test/test_retention_query_runner.py
@@ -907,6 +907,64 @@ def test_all_events(self):
             ],
         )
 
+    def test_all_events_target_first_time(self):
+        _create_person(team_id=self.team.pk, distinct_ids=["person1"])
+
+        _create_events(
+            self.team,
+            [
+                ("person1", _date(0)),
+                ("person1", _date(1)),
+                ("person1", _date(2)),
+            ],
+            "event1",
+        )
+
+        _create_events(
+            self.team,
+            [
+                ("person1", _date(2)),
+                ("person1", _date(3)),
+            ],
+            "event2",
+        )
+
+        result_all_events = self.run_query(
+            query={
+                "dateRange": {"date_to": _date(2, hour=6)},
+                "retentionFilter": {
+                    "retentionType": "retention_first_time",
+                    "totalIntervals": 4,
+                    "targetEntity": {"id": "event2", "type": "events"},
+                    "returningEntity": {"id": None, "name": "All events"},
+                },
+            }
+        )
+
+        result_specific_event = self.run_query(
+            query={
+                "dateRange": {"date_to": _date(2, hour=6)},
+                "retentionFilter": {
+                    "retentionType": "retention_first_time",
+                    "totalIntervals": 4,
+                    "targetEntity": {"id": "event2", "type": "events"},
+                    "returningEntity": {"id": "event2", "type": "events"},
+                },
+            }
+        )
+
+        self.assertEqual(
+            pluck(result_specific_event, "values", "count"),
+            [
+                [0, 0, 0, 0],
+                [0, 0, 0],
+                [0, 0],
+                [1],
+            ],
+        )
+
+        self.assertEqual(result_specific_event, result_all_events)
+
     def test_retention_people_basic(self):
         person1 = _create_person(team_id=self.team.pk, distinct_ids=["person1", "alias1"])
         _create_person(team_id=self.team.pk, distinct_ids=["person2"])