Update timeslot function

docs/en/sql-reference/functions/date-time-functions.md

@@ -2413,6 +2413,47 @@ The same as ‘today() - 1’.
 
 Rounds the time to the half hour.
 
+**Syntax**
+
+```sql
+timeSlot(time)
+```
+**Parameters**
+
+- `time`: Date and Time for which to round to the half hour. [Date](../data-types/date.md), [DateTime](../data-types/datetime.md), [Date32](../data-types/date32.md), [DateTime64](../data-types/datetime64.md).
+
+:::note
+Though this function can take values of the extended types `Date32` and `DateTime64` as an argument, passing a time outside the normal range (year `1970` to `2149` for `Date` / `2106` for `DateTime`) will produce wrong results.
+:::
+
+**Returned value**
+
+:::note
+The return type of `timeslot` is determined by the configuration parameter [enable_extended_results_for_datetime_functions](../../operations/settings/settings.md#enable-extended-results-for-datetime-functions) which is `0` by default.
+
+For:
+- `enable_extended_results_for_datetime_functions = 0` the return type is `DateTime`.
+- `enable_extended_results_for_datetime_functions = 1` the return type is `DateTime` if the argument type is a `Date` or `DateTime`, and returns `DateTime64` if the argument type is a `Date32` or `DateTime64`.
+:::
+
+**Example**
+
+Query:
+
+```sql
+SELECT timeSlot(toDateTime('2000-01-02 03:04:05', 'UTC'));
+```
+
+Result:
+
+```response
+┌─timeSlot(toDateTime('2000-01-02 03:04:05', 'UTC'))─┐
+│                                2000-01-02 03:00:00 │
+└────────────────────────────────────────────────────┘
+```
+
+
+
 ## toYYYYMM
 
 Converts a date or date with time to a UInt32 number containing the year and month number (YYYY \* 100 + MM). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.