Merge pull request #23457 from sevirov/sevirov-DOCSUP-8737-edit_and_translate_to_russian_explain

DOCSUP-8737: Edit and translate to Russian (EXPLAIN)

docs/en/sql-reference/statements/explain.md

@@ -5,7 +5,7 @@ toc_title: EXPLAIN
 
 # EXPLAIN Statement {#explain}
 
-Show the execution plan of a statement.
+Shows the execution plan of a statement.
 
 Syntax:
 
@@ -65,7 +65,7 @@ SelectWithUnionQuery (children 1)
 
 ### EXPLAIN SYNTAX {#explain-syntax}
 
-Return query after syntax optimizations.
+Returns query after syntax optimizations.
 
 Example:
 
@@ -88,15 +88,16 @@ FROM
 ) AS `--.s`
 CROSS JOIN system.numbers AS c
 ```
+
 ### EXPLAIN PLAN {#explain-plan}
 
 Dump query plan steps.
 
 Settings:
 
--  `header` — Print output header for step. Default: 0.
--  `description` — Print step description. Default: 1.
--  `actions` — Print detailed information about step actions. Default: 0.
+-  `header` — Prints output header for step. Default: 0.
+-  `description` — Prints step description. Default: 1.
+-  `actions` — Prints detailed information about step actions. Default: 0.
 
 Example:
 
@@ -115,15 +116,16 @@ Union
 ```
 
 !!! note "Note"
-  Step and query cost estimation is not supported.
+    Step and query cost estimation is not supported.
 
 ### EXPLAIN PIPELINE {#explain-pipeline}
 
 Settings:
 
--   `header` — Print header for each output port. Default: 0.
--   `graph` — Use DOT graph description language. Default: 0.
--   `compact` — Print graph in compact mode if graph is enabled. Default: 1.
+-   `header` — Prints header for each output port. Default: 0.
+-   `graph` — Prints a graph described in the [DOT](https://en.wikipedia.org/wiki/DOT_(graph_description_language)) graph description language. Default: 0.
+-   `compact` — Prints graph in compact mode if `graph` setting is enabled. Default: 1.
+-   `indexes` — Shows used indexes, the number of filtered parts, and granules for every index applied. Default: 0. Supported for [MergeTree](../../engines/table-engines/mergetree-family/mergetree.md) tables.
 
 Example:
 

docs/ru/sql-reference/statements/explain.md

@@ -0,0 +1,152 @@
+---
+toc_priority: 39
+toc_title: EXPLAIN
+---
+
+# EXPLAIN {#explain}
+
+Выводит план выполнения запроса.
+
+Синтаксис:
+
+```sql
+EXPLAIN [AST | SYNTAX | PLAN | PIPELINE] [setting = value, ...] SELECT ... [FORMAT ...]
+```
+
+Пример:
+
+```sql
+EXPLAIN SELECT sum(number) FROM numbers(10) UNION ALL SELECT sum(number) FROM numbers(10) ORDER BY sum(number) ASC FORMAT TSV;
+```
+
+```sql
+Union
+  Expression (Projection)
+    Expression (Before ORDER BY and SELECT)
+      Aggregating
+        Expression (Before GROUP BY)
+          SettingQuotaAndLimits (Set limits and quota after reading from storage)
+            ReadFromStorage (SystemNumbers)
+  Expression (Projection)
+    MergingSorted (Merge sorted streams for ORDER BY)
+      MergeSorting (Merge sorted blocks for ORDER BY)
+        PartialSorting (Sort each block for ORDER BY)
+          Expression (Before ORDER BY and SELECT)
+            Aggregating
+              Expression (Before GROUP BY)
+                SettingQuotaAndLimits (Set limits and quota after reading from storage)
+                  ReadFromStorage (SystemNumbers)
+```
+
+## Типы EXPLAIN {#explain-types}
+
+-  `AST` — абстрактное синтаксическое дерево.
+-  `SYNTAX` — текст запроса после оптимизации на уровне AST.
+-  `PLAN` — план выполнения запроса.
+-  `PIPELINE` — конвейер выполнения запроса.
+
+### EXPLAIN AST {#explain-ast}
+
+Дамп AST запроса.
+
+Пример:
+
+```sql
+EXPLAIN AST SELECT 1;
+```
+
+```sql
+SelectWithUnionQuery (children 1)
+ ExpressionList (children 1)
+  SelectQuery (children 1)
+   ExpressionList (children 1)
+    Literal UInt64_1
+```
+
+### EXPLAIN SYNTAX {#explain-syntax}
+
+Возвращает текст запроса после применения синтаксических оптимизаций.
+
+Пример:
+
+```sql
+EXPLAIN SYNTAX SELECT * FROM system.numbers AS a, system.numbers AS b, system.numbers AS c;
+```
+
+```sql
+SELECT
+    `--a.number` AS `a.number`,
+    `--b.number` AS `b.number`,
+    number AS `c.number`
+FROM
+(
+    SELECT
+        number AS `--a.number`,
+        b.number AS `--b.number`
+    FROM system.numbers AS a
+    CROSS JOIN system.numbers AS b
+) AS `--.s`
+CROSS JOIN system.numbers AS c
+```
+
+### EXPLAIN PLAN {#explain-plan}
+
+Дамп шагов выполнения запроса.
+
+Настройки:
+
+-  `header` — выводит выходной заголовок для шага. По умолчанию: 0.
+-  `description` — выводит описание шага. По умолчанию: 1.
+-  `actions` — выводит подробную информацию о действиях, выполняемых на данном шаге. По умолчанию: 0.
+
+Пример:
+
+```sql
+EXPLAIN SELECT sum(number) FROM numbers(10) GROUP BY number % 4;
+```
+
+```sql
+Union
+  Expression (Projection)
+  Expression (Before ORDER BY and SELECT)
+    Aggregating
+      Expression (Before GROUP BY)
+        SettingQuotaAndLimits (Set limits and quota after reading from storage)
+          ReadFromStorage (SystemNumbers)
+```
+
+!!! note "Примечание"
+    Оценка стоимости выполнения шага и запроса не поддерживается.
+
+### EXPLAIN PIPELINE {#explain-pipeline}
+
+Настройки:
+
+-   `header` — выводит заголовок для каждого выходного порта. По умолчанию: 0.
+-   `graph` — выводит граф, описанный на языке [DOT](https://ru.wikipedia.org/wiki/DOT_(язык)). По умолчанию: 0.
+-   `compact` — выводит граф в компактном режиме, если включена настройка `graph`. По умолчанию: 1.
+-   `indexes` — показывает используемые индексы, количество отфильтрованных кусков и гранул для каждого примененного индекса. По умолчанию: 0. Поддерживается для таблиц семейства [MergeTree](../../engines/table-engines/mergetree-family/mergetree.md).
+
+Пример:
+
+```sql
+EXPLAIN PIPELINE SELECT sum(number) FROM numbers_mt(100000) GROUP BY number % 4;
+```
+
+```sql
+(Union)
+(Expression)
+ExpressionTransform
+  (Expression)
+  ExpressionTransform
+    (Aggregating)
+    Resize 2 → 1
+      AggregatingTransform × 2
+        (Expression)
+        ExpressionTransform × 2
+          (SettingQuotaAndLimits)
+            (ReadFromStorage)
+            NumbersMt × 2 0 → 1
+```
+
+[Оригинальная статья](https://clickhouse.tech/docs/ru/sql-reference/statements/explain/) <!--hide-->