From 244876a00e73082c3b77137a0a16f665257aba48 Mon Sep 17 00:00:00 2001
From: Tyler White <50381805+IndexSeek@users.noreply.github.com>
Date: Sun, 13 Oct 2024 16:20:23 -0400
Subject: [PATCH] fix(mssql): exclude window frame from rank (#10302)

## Description of changes

Resolves an error where the RANK window function added a `ROWS BETWEEN
UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING` window frame, which is
unsupported by MSSQL.

> The <rows or range clause/> of the OVER clause cannot be specified for
the RANK function. For more information, see [OVER Clause
(Transact-SQL)](https://learn.microsoft.com/en-us/sql/t-sql/queries/select-over-clause-transact-sql?view=sql-server-ver16).

## Issues closed

Resolves #10291
---
 .../test_window/test_rank_no_window_frame/out.sql     |  5 +++++
 ibis/backends/mssql/tests/test_window.py              | 11 +++++++++++
 ibis/backends/sql/compilers/mssql.py                  |  2 ++
 3 files changed, 18 insertions(+)
 create mode 100644 ibis/backends/mssql/tests/snapshots/test_window/test_rank_no_window_frame/out.sql
 create mode 100644 ibis/backends/mssql/tests/test_window.py

diff --git a/ibis/backends/mssql/tests/snapshots/test_window/test_rank_no_window_frame/out.sql b/ibis/backends/mssql/tests/snapshots/test_window/test_rank_no_window_frame/out.sql
new file mode 100644
index 000000000000..489bd8f642e8
--- /dev/null
+++ b/ibis/backends/mssql/tests/snapshots/test_window/test_rank_no_window_frame/out.sql
@@ -0,0 +1,5 @@
+SELECT
+  [t0].[color],
+  [t0].[price],
+  RANK() OVER (PARTITION BY [t0].[color] ORDER BY CASE WHEN [t0].[price] IS NULL THEN 1 ELSE 0 END, [t0].[price] ASC) - 1 AS [MinRank()]
+FROM [diamonds_sample] AS [t0]
\ No newline at end of file
diff --git a/ibis/backends/mssql/tests/test_window.py b/ibis/backends/mssql/tests/test_window.py
new file mode 100644
index 000000000000..6b8aca351153
--- /dev/null
+++ b/ibis/backends/mssql/tests/test_window.py
@@ -0,0 +1,11 @@
+from __future__ import annotations
+
+import ibis
+
+
+def test_rank_no_window_frame(con, snapshot):
+    t = ibis.table(schema=dict(color=str, price=int), name="diamonds_sample")
+    expr = t.mutate(ibis.rank().over(group_by="color", order_by="price"))
+    sql = ibis.to_sql(expr, dialect="mssql")
+
+    snapshot.assert_match(sql, "out.sql")
diff --git a/ibis/backends/sql/compilers/mssql.py b/ibis/backends/sql/compilers/mssql.py
index aaee60a20cda..dd8d888d3442 100644
--- a/ibis/backends/sql/compilers/mssql.py
+++ b/ibis/backends/sql/compilers/mssql.py
@@ -21,6 +21,7 @@
 from ibis.backends.sql.dialects import MSSQL
 from ibis.backends.sql.rewrites import (
     exclude_unsupported_window_frame_from_ops,
+    exclude_unsupported_window_frame_from_rank,
     exclude_unsupported_window_frame_from_row_number,
     lower_sample,
     p,
@@ -68,6 +69,7 @@ class MSSQLCompiler(SQLGlotCompiler):
     rewrites = (
         exclude_unsupported_window_frame_from_ops,
         exclude_unsupported_window_frame_from_row_number,
+        exclude_unsupported_window_frame_from_rank,
         rewrite_rows_range_order_by_window,
         *SQLGlotCompiler.rewrites,
     )