From 72c72f131bcb2ea06f8224e50cd97663a8e05dec Mon Sep 17 00:00:00 2001
From: Andrey Fedorov <andrey.fedorov@snowflake.com>
Date: Mon, 21 Oct 2019 20:53:22 -0700
Subject: [PATCH] Fixes bug in time_slices to work with large queries

---
 migrations/v1_8_6-v1_8_8.md                   | 25 +++++++++++++++++++
 src/runners/tests/run_alerts.py               |  2 +-
 .../installer-queries/create-udtfs.sql.fmt    | 15 ++++++++---
 3 files changed, 38 insertions(+), 4 deletions(-)
 create mode 100644 migrations/v1_8_6-v1_8_8.md

diff --git a/migrations/v1_8_6-v1_8_8.md b/migrations/v1_8_6-v1_8_8.md
new file mode 100644
index 000000000..b96a672e6
--- /dev/null
+++ b/migrations/v1_8_6-v1_8_8.md
@@ -0,0 +1,25 @@
+## Bug fixes in data UDTF's
+
+Time slices would be buggy when running as part of a large query. To fix them, please run —
+
+~~~
+USE SCHEMA data;
+
+CREATE OR REPLACE FUNCTION time_slices (n NUMBER, s TIMESTAMP_NTZ, e TIMESTAMP_NTZ)
+RETURNS TABLE ( slice_start TIMESTAMP_NTZ, slice_end TIMESTAMP_NTZ )
+AS '
+  SELECT DATEADD(sec, DATEDIFF(sec, s, e) * ROW_NUMBER() OVER (ORDER BY SEQ4()) / n, s) AS slice_start
+       , DATEADD(sec, DATEDIFF(sec, s, e) * 1 / n, slice_start) AS slice_end
+  FROM TABLE(GENERATOR(ROWCOUNT => n))
+'
+;
+
+CREATE OR REPLACE FUNCTION time_slices (n NUMBER, s TIMESTAMP_LTZ, e TIMESTAMP_LTZ)
+RETURNS TABLE ( slice_start TIMESTAMP_LTZ, slice_end TIMESTAMP_LTZ )
+AS '
+  SELECT DATEADD(sec, DATEDIFF(sec, s, e) * ROW_NUMBER() OVER (ORDER BY SEQ4()) / n, s) AS slice_start
+       , DATEADD(sec, DATEDIFF(sec, s, e) * 1 / n, slice_start) AS slice_end
+  FROM TABLE(GENERATOR(ROWCOUNT => n))
+'
+;
+~~~
diff --git a/src/runners/tests/run_alerts.py b/src/runners/tests/run_alerts.py
index db36be0ec..9a30c60c3 100644
--- a/src/runners/tests/run_alerts.py
+++ b/src/runners/tests/run_alerts.py
@@ -220,7 +220,7 @@ def test_alert_runners_processor_and_dispatcher(
     assert len(query_rule_run_record) == 7  # 3 from samples + 4 test alert queries
 
     assert query_rule_run_record[0]['QUERY_NAME'] == 'ACTIVITY_BY_ADMIN_ALERT_QUERY'
-    queries_by_admin = 57
+    queries_by_admin = 58
     assert query_rule_run_record[0]['NUM_ALERTS_CREATED'] == queries_by_admin
 
     assert (
diff --git a/src/scripts/installer-queries/create-udtfs.sql.fmt b/src/scripts/installer-queries/create-udtfs.sql.fmt
index bb11d2efd..570c19413 100644
--- a/src/scripts/installer-queries/create-udtfs.sql.fmt
+++ b/src/scripts/installer-queries/create-udtfs.sql.fmt
@@ -1,9 +1,18 @@
 USE SCHEMA data;
 
-CREATE OR REPLACE FUNCTION time_slices (n NUMBER, s TIMESTAMP, e TIMESTAMP)
-RETURNS TABLE ( slice_start TIMESTAMP, slice_end TIMESTAMP )
+CREATE FUNCTION IF NOT EXISTS time_slices (n NUMBER, s TIMESTAMP_NTZ, e TIMESTAMP_NTZ)
+RETURNS TABLE ( slice_start TIMESTAMP_NTZ, slice_end TIMESTAMP_NTZ )
+AS '
+  SELECT DATEADD(sec, DATEDIFF(sec, s, e) * ROW_NUMBER() OVER (ORDER BY SEQ4()) / n, s) AS slice_start
+       , DATEADD(sec, DATEDIFF(sec, s, e) * 1 / n, slice_start) AS slice_end
+  FROM TABLE(GENERATOR(ROWCOUNT => n))
+'
+;
+
+CREATE FUNCTION IF NOT EXISTS time_slices (n NUMBER, s TIMESTAMP_LTZ, e TIMESTAMP_LTZ)
+RETURNS TABLE ( slice_start TIMESTAMP_LTZ, slice_end TIMESTAMP_LTZ )
 AS '
-  SELECT DATEADD(sec, DATEDIFF(sec, s, e) * SEQ4() / n, s) AS slice_start
+  SELECT DATEADD(sec, DATEDIFF(sec, s, e) * ROW_NUMBER() OVER (ORDER BY SEQ4()) / n, s) AS slice_start
        , DATEADD(sec, DATEDIFF(sec, s, e) * 1 / n, slice_start) AS slice_end
   FROM TABLE(GENERATOR(ROWCOUNT => n))
 '