Add arrayEnumerateUniqRanked and arrayEnumerateDenseRanked functions

docs/en/sql-reference/functions/array-functions.md

@@ -939,6 +939,66 @@ SELECT arrayEnumerateUniq([1, 1, 1, 2, 2, 2], [1, 1, 2, 1, 1, 2]) AS res
 
 This is necessary when using ARRAY JOIN with a nested data structure and further aggregation across multiple elements in this structure.
 
+## arrayEnumerateUniqRanked
+
+Returns an array the same size as the source array, indicating for each element what its position is among elements with the same value. It allows for enumeration of a multidimensional array with the ability to specify how deep to look inside the array.
+
+**Syntax**
+
+```sql
+arrayEnumerateUniqRanked(clear_depth, arr, max_array_depth)
+```
+
+**Parameters**
+
+- `clear_depth`: Enumerate elements at the specified level separately. Positive [Integer](../data-types/int-uint.md) less than or equal to `max_arr_depth`.
+- `arr`: N-dimensional array to enumerate. [Array](../data-types/array.md)
+- `max_array_depth`: The maximum effective depth. Positive [Integer](../data-types/int-uint.md) less than or equal to the depth of `arr`.
+
+**Example**
+
+With `clear_depth=1` and `max_array_depth=1`, the result of `arrayEnumerateUniqRanked` is identical to that which [`arrayEnumerateUniq`](#arrayenumerateuniqarr) would give for the same array.
+
+Query:
+
+``` sql
+SELECT arrayEnumerateUniqRanked(1, [1,2,1], 1);
+```
+
+Result:
+
+``` text
+[1,1,2]
+```
+
+In this example, `arrayEnumerateUniqRanked` is used to obtain an array indicating, for each element of the multidimensional array, what its position is among elements of the same value. For the first row of the passed array,`[1,2,3]`, the corresponding result is `[1,1,1]`, indicating that this is the first time `1`,`2` and `3` are encountered. For the second row of the provided array,`[2,2,1]`, the corresponding result is `[2,3,3]`, indicating that the number `2` is encountered for a second and third time, and `1` is encountered for the second time. Likewise, for the third row of the provided array `[3]` the corresponding result is `[2]` indicating that the number `3` is encountered for the second time. 
+
+Query:
+
+``` sql
+SELECT arrayEnumerateUniqRanked(1, [[1,2,3],[2,2,1],[3]], 2);
+```
+
+Result:
+
+``` text
+[[1,1,1],[2,3,2],[2]]
+```
+
+Changing `clear_depth=2`, results in elements being enumerated seperately for each row.
+
+Query:
+
+``` sql
+SELECT arrayEnumerateUniqRanked(2, [[1,2,3],[2,2,1],[3]], 2);
+```
+
+Result:
+
+``` text
+[[1,1,1],[1,2,1],[1]]
+```
+
 ## arrayPopBack
 
 Removes the last item from the array.
@@ -1478,7 +1538,7 @@ Result:
 ```
 ## arrayEnumerateDenseRanked
 
-Enumerates distinct values of the passed multidimensional array, looking inside at the specified depths. 
+Returns an array the same size as the source array, indicating where each element first appears in the source array. It allows for enumeration of a multidimensional array with the ability to specify how deep to look inside the array.
 
 **Syntax**
 
@@ -1488,7 +1548,7 @@ arrayEnumerateDenseRanked(clear_depth, arr, max_array_depth)
 
 **Parameters**
 
-- `clear_depth`: Enumerate elements at the specified level separately. (The enumeration counter is reset for each new element). Positive [Integer](../data-types/int-uint.md) less than or equal to `max_arr_depth`.
+- `clear_depth`: Enumerate elements at the specified level separately. Positive [Integer](../data-types/int-uint.md) less than or equal to `max_arr_depth`.
 - `arr`: N-dimensional array to enumerate. [Array](../data-types/array.md)
 - `max_array_depth`: The maximum effective depth. Positive [Integer](../data-types/int-uint.md) less than or equal to the depth of `arr`.
 
@@ -1508,18 +1568,33 @@ Result:
 [1,2,1,3]
 ```
 
-`arrayEnumerateDenseRanked` can be used to enumerate multidimensional arrays.
+In this example, `arrayEnumerateDenseRanked` is used to obtain an array indicating, for each element of the multidimensional array, what its position is among elements of the same value. For the first row of the passed array,`[10,10,30,20]`, the corresponding first row of the result is `[1,1,2,3]`, indicating that `10` is the first element encountered in position 1 and 2, `30` the second element encountered in position 3 and `20` is the third element encountered in position 4. For the second row, `[40, 50, 10, 30]`, the corresponding second row of the result is `[4,5,1,2]`, indicating that `40` and `50` are the fourth and fifth numbers encountered in position 1 and 2 of that row, that another `10` (the first encountered number) is in position 3 and `30` (the second number encountered) is in the last position. 
+
 
 Query:
 
 ``` sql
-SELECT arrayEnumerateDenseRanked(2,[[10, 20, 10, 30],[40, 50, 60, 70]],2);
+SELECT arrayEnumerateDenseRanked(1,[[10,10,30,20],[40,50,10,30]],2);
 ```
 
 Result:
 
 ``` text
-[[1,2,1,3],[4,5,6,7]]
+[[1,1,2,3],[4,5,1,2]]
+```
+
+Changing `clear_depth=2` results in the enumeration occuring separetely for each row anew.
+
+Query:
+
+``` sql
+SELECT arrayEnumerateDenseRanked(2,[[10,10,30,20],[40,50,10,30]],2);
+```
+
+Result:
+
+``` text
+[[1,1,2,3],[1,2,3,4]]
 ```
 
 ## arrayIntersect(arr)