From 0730e685b0ae976e72155858865a5953ef55bb4b Mon Sep 17 00:00:00 2001
From: Alexander Kuzmenkov <akuzm@yandex-team.ru>
Date: Wed, 4 Aug 2021 17:45:32 +0300
Subject: [PATCH] Mark window functions ready for general use.

---
 .../sql-reference/window-functions/index.md   |  3 ---
 src/Core/Settings.h                           |  1 -
 src/Interpreters/ExpressionAnalyzer.cpp       | 12 -----------
 tests/performance/window_functions.xml        |  4 ----
 ...mize_distributed_group_by_sharding_key.sql |  2 +-
 ...568_window_functions_distributed.reference |  1 -
 .../01568_window_functions_distributed.sql    |  2 --
 .../01571_window_functions.reference          |  2 +-
 .../0_stateless/01571_window_functions.sql    |  1 -
 .../01591_window_functions.reference          |  2 --
 .../0_stateless/01591_window_functions.sql    |  2 --
 .../01592_long_window_functions1.sql          |  1 -
 .../0_stateless/01592_window_functions.sql    |  2 --
 ...802_rank_corr_mann_whitney_over_window.sql |  2 --
 .../window_functions/tests/common.py          | 20 -------------------
 .../window_functions/tests/feature.py         |  3 ---
 16 files changed, 2 insertions(+), 58 deletions(-)

diff --git a/docs/en/sql-reference/window-functions/index.md b/docs/en/sql-reference/window-functions/index.md
index dcab019c9d5..e62808a46bd 100644
--- a/docs/en/sql-reference/window-functions/index.md
+++ b/docs/en/sql-reference/window-functions/index.md
@@ -5,9 +5,6 @@ toc_title: Window Functions
 
 # [experimental] Window Functions
 
-!!! warning "Warning"
-    This is an experimental feature that is currently in development and is not ready for general use. It will change in unpredictable backwards-incompatible ways in the future releases. Set `allow_experimental_window_functions = 1` to enable it.
-
 ClickHouse supports the standard grammar for defining windows and window functions. The following features are currently supported:
 
 | Feature | Support or workaround |
diff --git a/src/Core/Settings.h b/src/Core/Settings.h
index c8befbb81b2..d311b0b5c60 100644
--- a/src/Core/Settings.h
+++ b/src/Core/Settings.h
@@ -449,7 +449,6 @@ class IColumn;
     M(Bool, optimize_skip_merged_partitions, false, "Skip partitions with one part with level > 0 in optimize final", 0) \
     M(Bool, optimize_on_insert, true, "Do the same transformation for inserted block of data as if merge was done on this block.", 0) \
     M(Bool, allow_experimental_map_type, true, "Obsolete setting, does nothing.", 0) \
-    M(Bool, allow_experimental_window_functions, false, "Allow experimental window functions", 0) \
     M(Bool, allow_experimental_projection_optimization, false, "Enable projection optimization when processing SELECT queries", 0) \
     M(Bool, force_optimize_projection, false, "If projection optimization is enabled, SELECT queries need to use projection", 0) \
     M(Bool, async_socket_for_remote, true, "Asynchronously read from socket executing remote query", 0) \
diff --git a/src/Interpreters/ExpressionAnalyzer.cpp b/src/Interpreters/ExpressionAnalyzer.cpp
index 875a7bef862..ad1ee703785 100644
--- a/src/Interpreters/ExpressionAnalyzer.cpp
+++ b/src/Interpreters/ExpressionAnalyzer.cpp
@@ -608,18 +608,6 @@ void makeWindowDescriptionFromAST(const Context & context,
 
 void ExpressionAnalyzer::makeWindowDescriptions(ActionsDAGPtr actions)
 {
-    // Convenient to check here because at least we have the Context.
-    if (!syntax->window_function_asts.empty() &&
-        !getContext()->getSettingsRef().allow_experimental_window_functions)
-    {
-        throw Exception(ErrorCodes::NOT_IMPLEMENTED,
-            "The support for window functions is experimental and will change"
-            " in backwards-incompatible ways in the future releases. Set"
-            " allow_experimental_window_functions = 1 to enable it."
-            " While processing '{}'",
-            syntax->window_function_asts[0]->formatForErrorMessage());
-    }
-
     // Window definitions from the WINDOW clause
     const auto * select_query = query->as<ASTSelectQuery>();
     if (select_query && select_query->window())
diff --git a/tests/performance/window_functions.xml b/tests/performance/window_functions.xml
index 6be3d59e2b0..e3d30d96ec3 100644
--- a/tests/performance/window_functions.xml
+++ b/tests/performance/window_functions.xml
@@ -3,10 +3,6 @@
         <table_exists>hits_100m_single</table_exists>
     </preconditions>
 
-    <settings>
-        <allow_experimental_window_functions>1</allow_experimental_window_functions>
-    </settings>
-
     <!--
         For some counters, find top 10 users by the numer of records.
         First with LIMIT BY, next with window functions.
diff --git a/tests/queries/0_stateless/01244_optimize_distributed_group_by_sharding_key.sql b/tests/queries/0_stateless/01244_optimize_distributed_group_by_sharding_key.sql
index 4719119165a..1dcdd795bc1 100644
--- a/tests/queries/0_stateless/01244_optimize_distributed_group_by_sharding_key.sql
+++ b/tests/queries/0_stateless/01244_optimize_distributed_group_by_sharding_key.sql
@@ -116,7 +116,7 @@ select distinct on (k1) k2 from remote('127.{1,2}', view(select 1 k1, 2 k2, 3 v)
 
 -- window functions
 select 'window functions';
-select key, sum(sum(value)) over (rows unbounded preceding) from dist_01247 group by key settings allow_experimental_window_functions=1;
+select key, sum(sum(value)) over (rows unbounded preceding) from dist_01247 group by key;
 
 drop table dist_01247;
 drop table data_01247;
diff --git a/tests/queries/0_stateless/01568_window_functions_distributed.reference b/tests/queries/0_stateless/01568_window_functions_distributed.reference
index 483e84a2bee..0b439ef759a 100644
--- a/tests/queries/0_stateless/01568_window_functions_distributed.reference
+++ b/tests/queries/0_stateless/01568_window_functions_distributed.reference
@@ -1,5 +1,4 @@
 -- { echo }
-set allow_experimental_window_functions = 1;
 select row_number() over (order by dummy) from (select * from remote('127.0.0.{1,2}', system, one));
 1
 2
diff --git a/tests/queries/0_stateless/01568_window_functions_distributed.sql b/tests/queries/0_stateless/01568_window_functions_distributed.sql
index 6f38597a7a3..5e20c57d23d 100644
--- a/tests/queries/0_stateless/01568_window_functions_distributed.sql
+++ b/tests/queries/0_stateless/01568_window_functions_distributed.sql
@@ -1,6 +1,4 @@
 -- { echo }
-set allow_experimental_window_functions = 1;
-
 select row_number() over (order by dummy) from (select * from remote('127.0.0.{1,2}', system, one));
 
 select row_number() over (order by dummy) from remote('127.0.0.{1,2}', system, one);
diff --git a/tests/queries/0_stateless/01571_window_functions.reference b/tests/queries/0_stateless/01571_window_functions.reference
index e9feb9295df..420f7575a52 100644
--- a/tests/queries/0_stateless/01571_window_functions.reference
+++ b/tests/queries/0_stateless/01571_window_functions.reference
@@ -1,6 +1,6 @@
 -- { echo }
 -- Another test for window functions because the other one is too long.
-set allow_experimental_window_functions = 1;
+
 -- some craziness with a mix of materialized and unmaterialized const columns
 -- after merging sorted transform, that used to break the peer group detection in
 -- the window transform.
diff --git a/tests/queries/0_stateless/01571_window_functions.sql b/tests/queries/0_stateless/01571_window_functions.sql
index 56ead7a1188..4aaba19100a 100644
--- a/tests/queries/0_stateless/01571_window_functions.sql
+++ b/tests/queries/0_stateless/01571_window_functions.sql
@@ -1,6 +1,5 @@
 -- { echo }
 -- Another test for window functions because the other one is too long.
-set allow_experimental_window_functions = 1;
 
 -- some craziness with a mix of materialized and unmaterialized const columns
 -- after merging sorted transform, that used to break the peer group detection in
diff --git a/tests/queries/0_stateless/01591_window_functions.reference b/tests/queries/0_stateless/01591_window_functions.reference
index 669a7e4f32f..1249ea55cdc 100644
--- a/tests/queries/0_stateless/01591_window_functions.reference
+++ b/tests/queries/0_stateless/01591_window_functions.reference
@@ -1,6 +1,4 @@
 -- { echo }
-
-set allow_experimental_window_functions = 1;
 -- just something basic
 select number, count() over (partition by intDiv(number, 3) order by number rows unbounded preceding) from numbers(10);
 0	1
diff --git a/tests/queries/0_stateless/01591_window_functions.sql b/tests/queries/0_stateless/01591_window_functions.sql
index b9456563c63..7e47762facd 100644
--- a/tests/queries/0_stateless/01591_window_functions.sql
+++ b/tests/queries/0_stateless/01591_window_functions.sql
@@ -1,7 +1,5 @@
 -- { echo }
 
-set allow_experimental_window_functions = 1;
-
 -- just something basic
 select number, count() over (partition by intDiv(number, 3) order by number rows unbounded preceding) from numbers(10);
 
diff --git a/tests/queries/0_stateless/01592_long_window_functions1.sql b/tests/queries/0_stateless/01592_long_window_functions1.sql
index bb0f77ff60a..14fe3affed3 100644
--- a/tests/queries/0_stateless/01592_long_window_functions1.sql
+++ b/tests/queries/0_stateless/01592_long_window_functions1.sql
@@ -1,6 +1,5 @@
 drop table if exists stack;
 
-set allow_experimental_window_functions = 1;
 set max_insert_threads = 4;
 
 create table stack(item_id Int64, brand_id Int64, rack_id Int64, dt DateTime, expiration_dt DateTime, quantity UInt64)
diff --git a/tests/queries/0_stateless/01592_window_functions.sql b/tests/queries/0_stateless/01592_window_functions.sql
index 8d5033fc821..b05b04628d2 100644
--- a/tests/queries/0_stateless/01592_window_functions.sql
+++ b/tests/queries/0_stateless/01592_window_functions.sql
@@ -1,5 +1,3 @@
-set allow_experimental_window_functions = 1;
-
 drop table if exists product_groups;
 drop table if exists products;
 
diff --git a/tests/queries/0_stateless/01802_rank_corr_mann_whitney_over_window.sql b/tests/queries/0_stateless/01802_rank_corr_mann_whitney_over_window.sql
index 24ee9282ac0..4b8bf0844a3 100644
--- a/tests/queries/0_stateless/01802_rank_corr_mann_whitney_over_window.sql
+++ b/tests/queries/0_stateless/01802_rank_corr_mann_whitney_over_window.sql
@@ -1,7 +1,5 @@
 DROP TABLE IF EXISTS 01802_empsalary;
 
-SET allow_experimental_window_functions=1;
-
 CREATE TABLE 01802_empsalary
 (
     `depname` LowCardinality(String),
diff --git a/tests/testflows/window_functions/tests/common.py b/tests/testflows/window_functions/tests/common.py
index 3a6ac95bd9b..3ed4f794ada 100644
--- a/tests/testflows/window_functions/tests/common.py
+++ b/tests/testflows/window_functions/tests/common.py
@@ -386,23 +386,3 @@ def create_table(self, name, statement, on_cluster=False):
                 node.query(f"DROP TABLE IF EXISTS {name} ON CLUSTER {on_cluster}")
             else:
                 node.query(f"DROP TABLE IF EXISTS {name}")
-
-@TestStep(Given)
-def allow_experimental_window_functions(self):
-    """Set allow_experimental_window_functions = 1
-    """
-    setting = ("allow_experimental_window_functions", 1)
-    default_query_settings = None
-
-    try:
-        with By("adding allow_experimental_window_functions to the default query settings"):
-            default_query_settings = getsattr(current().context, "default_query_settings", [])
-            default_query_settings.append(setting)
-        yield
-    finally:
-        with Finally("I remove allow_experimental_window_functions from the default query settings"):
-            if default_query_settings:
-                try:
-                    default_query_settings.pop(default_query_settings.index(setting))
-                except ValueError:
-                    pass
diff --git a/tests/testflows/window_functions/tests/feature.py b/tests/testflows/window_functions/tests/feature.py
index 124660e8802..e9f137360b8 100755
--- a/tests/testflows/window_functions/tests/feature.py
+++ b/tests/testflows/window_functions/tests/feature.py
@@ -17,9 +17,6 @@ def feature(self, distributed, node="clickhouse1"):
     self.context.distributed = distributed
     self.context.node = self.context.cluster.node(node)
 
-    with Given("I allow experimental window functions"):
-        allow_experimental_window_functions()
-
     with And("employee salary table"):
         empsalary_table(distributed=distributed)