Add settings to control nesting level for shards skipping optimization

- optimize_skip_unused_shards_nesting (allows control nesting level for
  shards skipping optimization)
- force_skip_optimize_shards_nesting (allows control nesting level for
  checking was shards skipped or not)
- deprecates force_skip_optimize_shards_no_nested

docs/en/operations/settings/settings.md

@@ -1126,6 +1126,18 @@ Possible values:
 
 Default value: 0
 
+## optimize\_skip\_unused\_shards\_nesting {#optimize-skip-unused-shards-nesting}
+
+Controls nesting level for [`optimize_skip_unused_shards`](#optimize-skip-unused-shards) (hence still requires [`optimize_skip_unused_shards`](#optimize-skip-unused-shards)).
+
+Possible values:
+
+-   0 — Disabled.
+-   1 — Enables `optimize_skip_unused_shards` only for the first level
+-   2 — Enables `optimize_skip_unused_shards` up to the second level
+
+Default value: 0
+
 ## force\_optimize\_skip\_unused\_shards {#force-optimize-skip-unused-shards}
 
 Enables or disables query execution if [optimize\_skip\_unused\_shards](#optimize-skip-unused-shards) is enabled and skipping of unused shards is not possible. If the skipping is not possible and the setting is enabled, an exception will be thrown.
@@ -1138,16 +1150,13 @@ Possible values:
 
 Default value: 0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
+## force\_optimize\_skip\_unused\_shards\_nesting {#settings-force_optimize_skip_unused_shards_nesting}
 
-Reset [`optimize_skip_unused_shards`](#optimize-skip-unused-shards) for nested `Distributed` table
+Controls nesting level for [`force_optimize_skip_unused_shards`](#force-optimize-skip-unused-shards) (hence still requires [`force_optimize_skip_unused_shards`](#force-optimize-skip-unused-shards)).
 
-Possible values:
-
--   1 — Enabled.
--   0 — Disabled.
-
-Default value: 0.
+-   Type: unsigned int
+-   1 — Enables `force_optimize_skip_unused_shards_nesting` only for the first level
+-   2 — Enables `force_optimize_skip_unused_shards_nesting` up to the second level
 
 ## optimize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 

docs/es/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ Valores posibles:
 
 Valor predeterminado: 0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
-
-Restablecer [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) para anidados `Distributed` tabla
-
-Valores posibles:
-
--   1 — Enabled.
--   0 — Disabled.
-
-Valor predeterminado: 0.
-
 ## Optize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 
 Habilita o deshabilita el lanzamiento de una excepción [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) la consulta no realizó una fusión.

docs/fa/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ The results of the compilation are saved in the build directory in the form of .
 
 مقدار پیشفرض: 0
 
-## به زور \_بهتیتیتیتی\_سکیپ\_اس\_ش\_شارد\_مایش داده میشود {#settings-force_optimize_skip_unused_shards_no_nested}
-
-بازنشانی [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) برای تو در تو `Distributed` جدول
-
-مقادیر ممکن:
-
--   1 — Enabled.
--   0 — Disabled.
-
-مقدار پیش فرض: 0.
-
 ## ا\_فزون\_ف\_کوپ {#setting-optimize_throw_if_noop}
 
 را قادر می سازد و یا غیر فعال پرتاب یک استثنا اگر یک [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) پرس و جو یک ادغام انجام نمی.

docs/fr/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ Valeurs possibles:
 
 Valeur par défaut: 0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
-
-Réinitialiser [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) pour imbriquée `Distributed` table
-
-Valeurs possibles:
-
--   1 — Enabled.
--   0 — Disabled.
-
-Valeur par défaut: 0.
-
 ## optimize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 
 Active ou désactive le lancement d'une exception si [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) la requête n'a pas effectué de fusion.

docs/ja/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ PREWHERE/WHEREにシャーディングキー条件があるSELECTクエリの未
 
 デフォルト値:0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
-
-リセット [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) 入れ子の場合 `Distributed` テーブル
-
-可能な値:
-
--   1 — Enabled.
--   0 — Disabled.
-
-デフォルト値は0です。
-
 ## optimize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 
 例外のスローを有効または無効にします。 [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) クエリがマージを実行しませんでした。

docs/tr/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ Olası değerler:
 
 Varsayılan değer: 0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
-
-Sıfırlamak [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) iç içe geçmiş için `Distributed` Tablo
-
-Olası değerler:
-
--   1 — Enabled.
--   0 — Disabled.
-
-Varsayılan değer: 0.
-
 ## optimize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 
 Bir özel durum atmayı etkinleştirir veya devre dışı bırakır. [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) sorgu birleştirme gerçekleştirmedi.

docs/zh/operations/settings/settings.md

@@ -1048,17 +1048,6 @@ ClickHouse生成异常
 
 默认值：0
 
-## force\_optimize\_skip\_unused\_shards\_no\_nested {#settings-force_optimize_skip_unused_shards_no_nested}
-
-重置 [`optimize_skip_unused_shards`](#settings-force_optimize_skip_unused_shards) 对于嵌套 `Distributed` 表
-
-可能的值:
-
--   1 — Enabled.
--   0 — Disabled.
-
-默认值：0。
-
 ## optimize\_throw\_if\_noop {#setting-optimize_throw_if_noop}
 
 启用或禁用抛出异常，如果 [OPTIMIZE](../../sql-reference/statements/misc.md#misc_operations-optimize) 查询未执行合并。

src/Core/Settings.h

@@ -121,10 +121,11 @@ struct Settings : public SettingsCollection<Settings>
     \
     M(SettingBool, distributed_group_by_no_merge, false, "Do not merge aggregation states from different servers for distributed query processing - in case it is for certain that there are different keys on different shards.", 0) \
     M(SettingBool, parallel_distributed_insert_select, false, "If true, distributed insert select query in the same cluster will be processed on local tables on every shard", 0) \
-    M(SettingUInt64, optimize_skip_unused_shards, 0, "Assumes that data is distributed by sharding_key. Optimization to skip unused shards if SELECT query filters by sharding_key (if 1 - includes nested Distributed, 2 - disable for nested Distributed).", 0) \
     M(SettingBool, optimize_distributed_group_by_sharding_key, false, "Optimize GROUP BY sharding_key queries (by avodiing costly aggregation on the initiator server).", 0) \
+    M(SettingBool, optimize_skip_unused_shards, false, "Assumes that data is distributed by sharding_key. Optimization to skip unused shards if SELECT query filters by sharding_key.", 0) \
     M(SettingUInt64, force_optimize_skip_unused_shards, 0, "Throw an exception if unused shards cannot be skipped (1 - throw only if the table has the sharding key, 2 - always throw.", 0) \
-    M(SettingBool, force_optimize_skip_unused_shards_no_nested, false, "Do not apply force_optimize_skip_unused_shards for nested Distributed tables.", 0) \
+    M(SettingUInt64, optimize_skip_unused_shards_nesting, 0, "Same as optimize_skip_unused_shards, but accept nesting level until which it will work.", 0) \
+    M(SettingUInt64, force_optimize_skip_unused_shards_nesting, 0, "Same as force_optimize_skip_unused_shards, but accept nesting level until which it will work.", 0) \
     \
     M(SettingBool, input_format_parallel_parsing, true, "Enable parallel parsing for some data formats.", 0) \
     M(SettingUInt64, min_chunk_bytes_for_parallel_parsing, (10 * 1024 * 1024), "The minimum chunk size in bytes, which each thread will parse in parallel.", 0) \
@@ -395,6 +396,7 @@ struct Settings : public SettingsCollection<Settings>
     M(SettingBool, partial_merge_join, false, "Obsolete. Use join_algorithm='prefer_partial_merge' instead.", 0) \
     M(SettingUInt64, max_memory_usage_for_all_queries, 0, "Obsolete. Will be removed after 2020-10-20", 0) \
     \
+    M(SettingBool, force_optimize_skip_unused_shards_no_nested, false, "Obsolete setting, does nothing. Will be removed after 2020-12-01. Use force_optimize_skip_unused_shards_nesting instead.", 0) \
     M(SettingBool, experimental_use_processors, true, "Obsolete setting, does nothing. Will be removed after 2020-11-29.", 0)
 
 #define FORMAT_FACTORY_SETTINGS(M)                                            \

src/Interpreters/ClusterProxy/executeQuery.cpp

@@ -17,8 +17,6 @@ namespace ClusterProxy
 
 Context removeUserRestrictionsFromSettings(const Context & context, const Settings & settings, Poco::Logger * log)
 {
-    static const UInt64 OPTIMIZE_SKIP_UNUSED_SHARDS_NO_NESTED = 2;
-
     Settings new_settings = settings;
     new_settings.queue_max_wait_ms = Cluster::saturate(new_settings.queue_max_wait_ms, settings.max_execution_time);
 
@@ -30,22 +28,44 @@ Context removeUserRestrictionsFromSettings(const Context & context, const Settin
     new_settings.max_concurrent_queries_for_user.changed = false;
     new_settings.max_memory_usage_for_user.changed = false;
 
-    if (settings.force_optimize_skip_unused_shards_no_nested)
+    if (settings.force_optimize_skip_unused_shards_nesting)
     {
-        new_settings.force_optimize_skip_unused_shards = 0;
-        new_settings.force_optimize_skip_unused_shards.changed = false;
-
-        if (log)
-            LOG_TRACE(log, "Disabling force_optimize_skip_unused_shards (due to force_optimize_skip_unused_shards_no_nested)");
+        if (new_settings.force_optimize_skip_unused_shards_nesting == 1)
+        {
+            new_settings.force_optimize_skip_unused_shards = 0;
+            new_settings.force_optimize_skip_unused_shards.changed = false;
+
+            if (log)
+                LOG_TRACE(log, "Disabling force_optimize_skip_unused_shards for nested queries (force_optimize_skip_unused_shards_nesting exceeded)");
+        }
+        else
+        {
+            new_settings.force_optimize_skip_unused_shards_nesting.value--;
+            new_settings.force_optimize_skip_unused_shards_nesting.changed = true;
+
+            if (log)
+                LOG_TRACE(log, "force_optimize_skip_unused_shards_nesting is now {}", new_settings.force_optimize_skip_unused_shards_nesting);
+        }
     }
 
-    if (settings.optimize_skip_unused_shards == OPTIMIZE_SKIP_UNUSED_SHARDS_NO_NESTED)
+    if (settings.optimize_skip_unused_shards_nesting)
     {
-        new_settings.optimize_skip_unused_shards = 0;
-        new_settings.optimize_skip_unused_shards.changed = false;
-
-        if (log)
-            LOG_TRACE(log, "Disabling optimize_skip_unused_shards (due to optimize_skip_unused_shards=2)");
+        if (new_settings.optimize_skip_unused_shards_nesting == 1)
+        {
+            new_settings.optimize_skip_unused_shards = 0;
+            new_settings.optimize_skip_unused_shards.changed = false;
+
+            if (log)
+                LOG_TRACE(log, "Disabling optimize_skip_unused_shards for nested queries (optimize_skip_unused_shards_nesting exceeded)");
+        }
+        else
+        {
+            new_settings.optimize_skip_unused_shards_nesting.value--;
+            new_settings.optimize_skip_unused_shards_nesting.changed = true;
+
+            if (log)
+                LOG_TRACE(log, "optimize_skip_unused_shards_nesting is now {}", new_settings.optimize_skip_unused_shards_nesting);
+        }
     }
 
     Context new_context(context);

tests/queries/0_stateless/01071_force_optimize_skip_unused_shards.sql

@@ -41,7 +41,7 @@ create table data2_01071 (key Int, sub_key Int) Engine=Null();
 create table dist2_layer_01071 as data2_01071 Engine=Distributed(test_cluster_two_shards, currentDatabase(), data2_01071, sub_key%2);
 create table dist2_01071 as data2_01071 Engine=Distributed(test_cluster_two_shards, currentDatabase(), dist2_layer_01071, key%2);
 select * from dist2_01071 where key = 1; -- { serverError 507 }
-set force_optimize_skip_unused_shards_no_nested=1;
+set force_optimize_skip_unused_shards_nesting=1;
 select * from dist2_01071 where key = 1;
 drop table if exists data2_01071;
 drop table if exists dist2_layer_01071;

tests/queries/0_stateless/01319_optimize_skip_unused_shards_no_nested.sql → tests/queries/0_stateless/01319_optimize_skip_unused_shards_nesting.sql

@@ -4,13 +4,19 @@ drop table if exists dist_layer_01319;
 
 create table data_01319 (key Int, sub_key Int) Engine=Null();
 
-set force_optimize_skip_unused_shards=2;
-set optimize_skip_unused_shards=1;
-
 create table dist_layer_01319 as data_01319 Engine=Distributed(test_cluster_two_shards, currentDatabase(), data_01319, sub_key);
 -- test_unavailable_shard here to check that optimize_skip_unused_shards always
 -- remove some nodes from the cluster for the first nesting level
 create table dist_01319 as data_01319 Engine=Distributed(test_unavailable_shard, currentDatabase(), dist_layer_01319, key+1);
+
+set optimize_skip_unused_shards=1;
+set force_optimize_skip_unused_shards=1;
+
+set force_optimize_skip_unused_shards_nesting=2;
+set optimize_skip_unused_shards_nesting=2;
 select * from dist_01319 where key = 1; -- { serverError 507 }
-set optimize_skip_unused_shards=2; -- no nested
+set force_optimize_skip_unused_shards_nesting=1;
+select * from dist_01319 where key = 1;
+set force_optimize_skip_unused_shards_nesting=2;
+set optimize_skip_unused_shards_nesting=1;
 select * from dist_01319 where key = 1;