Old task

docs/en/query_language/alter.md

@@ -21,7 +21,7 @@ The following actions are supported:
 - [COMMENT COLUMN](#alter_comment-column) — Adds a text comment to the column.
 - [MODIFY COLUMN](#alter_modify-column) — Changes column's type and/or default expression.
 
-Detailed description of these actions is shown below.
+These actions are described in detail below.
 
 #### ADD COLUMN {#alter_add-column}
 
@@ -127,7 +127,7 @@ The `ALTER` query for changing columns is replicated. The instructions are saved
 
 The `ALTER` query lets you create and delete separate elements (columns) in nested data structures, but not whole nested data structures. To add a nested data structure, you can add columns with a name like `name.nested_name` and the type `Array(T)`. A nested data structure is equivalent to multiple array columns with a name that has the same prefix before the dot.
 
-There is no support for deleting columns in the primary key or the sampling key (columns that are used in the `ENGINE` expression). Changing the type for columns that are included in the primary key is only possible if this change does not cause the data to be modified (for example, it is allowed to add values to an Enum or to change a type from `DateTime` to `UInt32`).
+There is no support for deleting columns in the primary key or the sampling key (columns that are used in the `ENGINE` expression). Changing the type for columns that are included in the primary key is only possible if this change does not cause the data to be modified (for example, you are allowed to add values to an Enum or to change a type from `DateTime` to `UInt32`).
 
 If the `ALTER` query is not sufficient to make the table changes you need, you can create a new table, copy the data to it using the [INSERT SELECT](insert_into.md#insert_query_insert-select) query, then switch the tables using the [RENAME](misc.md#misc_operations-rename) query and delete the old table. You can use the [clickhouse-copier](../operations/utils/clickhouse-copier.md) as an alternative to the `INSERT SELECT` query. 
 

docs/en/query_language/functions/higher_order_functions.md

@@ -12,16 +12,16 @@ A lambda function that accepts multiple arguments can be passed to a higher-orde
 
 For some functions, such as [arrayCount](#higher_order_functions-array-count) or [arraySum](#higher_order_functions-array-count), the first argument (the lambda function) can be omitted. In this case, identical mapping is assumed.
 
-A lamdba function can't be omitted for the following functions:
+A lambda function can't be omitted for the following functions:
 
-- [arrayMap](#higher_order_functions-array-count)
+- [arrayMap](#higher_order_functions-array-map)
 - [arrayFilter](#higher_order_functions-array-filter)
 - [arrayFirst](#higher_order_functions-array-first)
 - [arrayFirstIndex](#higher_order_functions-array-first-index)
 
 ### arrayMap(func, arr1, ...) {#higher_order_functions-array-map}
 
-Returns an array obtained from the original application of the 'func' function to each element in the 'arr' array. 
+Returns an array obtained from the original application of the `func` function to each element in the `arr` array. 
 
 Examples:
 
@@ -41,6 +41,9 @@ SELECT arrayMap((x, y) -> (x, y), [1, 2, 3], [4, 5, 6]) AS res
 │ [(1,4),(2,5),(3,6)] │
 └─────────────────────┘
 ```
+
+Note that the first argument (lambda function) can't be omitted in the `arrayMap` function.
+
 ### arrayFilter(func, arr1, ...) {#higher_order_functions-array-filter}
 
 Returns an array containing only the elements in `arr1` for which `func` returns something other than 0.
@@ -72,6 +75,8 @@ SELECT
 └─────┘
 ```
 
+Note that the first argument (lambda function) can't be omitted in the `arrayFilter` function.
+
 ### arrayCount(\[func,\] arr1, ...) {#higher_order_functions-array-count}
 
 Returns the number of elements in the arr array for which func returns something other than 0. If 'func' is not specified, it returns the number of non-zero elements in the array.
@@ -92,10 +97,14 @@ Returns the sum of the 'func' values. If the function is omitted, it just return
 
 Returns the first element in the 'arr1' array for which 'func' returns something other than 0.
 
+Note that the first argument (lambda function) can't be omitted in the `arrayFirst` function.
+
 ### arrayFirstIndex(func, arr1, ...) {#higher_order_functions-array-first-index}
 
 Returns the index of the first element in the 'arr1' array for which 'func' returns something other than 0.
 
+Note that the first argument (lambda function) can't be omitted in the `arrayFirstIndex` function.
+
 ### arrayCumSum(\[func,\] arr1, ...)
 
 Returns an array of partial sums of elements in the source array (a running sum). If the `func` function is specified, then the values of the array elements are converted by this function before summing.

docs/ru/query_language/functions/higher_order_functions.md

@@ -14,7 +14,7 @@
 
 Для функций, перечисленных ниже, лямбда-функцию должна быть указана всегда:
 
-- [arrayMap](#higher_order_functions-array-count)
+- [arrayMap](#higher_order_functions-array-map)
 - [arrayFilter](#higher_order_functions-array-filter)
 - [arrayFirst](#higher_order_functions-array-first)
 - [arrayFirstIndex](#higher_order_functions-array-first-index)
@@ -43,6 +43,8 @@ SELECT arrayMap((x, y) -> (x, y), [1, 2, 3], [4, 5, 6]) AS res
 └─────────────────────┘
 ```
 
+Обратите внимание, что у функции `arrayMap` первый аргумент (лямбда-функция) не может быть опущен.
+
 ### arrayFilter(func, arr1, ...) {#higher_order_functions-array-filter}
 
 Вернуть массив, содержащий только те элементы массива `arr1`, для которых функция `func`  возвращает не 0.
@@ -74,6 +76,8 @@ SELECT
 └─────┘
 ```
 
+Обратите внимание, что у функции `arrayFilter` первый аргумент (лямбда-функция) не может быть опущен.
+
 ### arrayCount(\[func,\] arr1, ...)
 Вернуть количество элементов массива `arr`, для которых функция func возвращает не 0. Если func не указана - вернуть количество ненулевых элементов массива.
 
@@ -89,10 +93,14 @@ SELECT
 ### arrayFirst(func, arr1, ...) {#higher_order_functions-array-first}
 Вернуть первый элемент массива `arr1`, для которого функция func возвращает не 0.
 
+Обратите внимание, что у функции `arrayFirst` первый аргумент (лямбда-функция) не может быть опущен.
+
 ### arrayFirstIndex(func, arr1, ...) {#higher_order_functions-array-first-index}
 
 Вернуть индекс первого элемента массива `arr1`, для которого функция func возвращает не 0.
 
+Обратите внимание, что у функции `arrayFirstFilter` первый аргумент (лямбда-функция) не может быть опущен.
+
 ### arrayCumSum(\[func,\] arr1, ...)
 
 Возвращает массив из частичных сумм элементов исходного массива (сумма с накоплением). Если указана функция `func`, то значения элементов массива преобразуются этой функцией перед суммированием.