Create calculated columns and append them to the result set.
| extend alias1 = expression1, alias2 = expression2, alias3 = ...
|Alias||string||The name of the column to add or update.|
|Expression||expression||A calculation over the columns of the dataset.|
A copy of the input dataset result, such that:
- Column names noted by extend that already exist in the input are removed and appended as their new calculated values.
- Column names noted by extend that do not exist in the input are appended as their new calculated values.
['http-logs'] | extend upper_ct = toupper(content_type)
['http-logs'] | extend extension = extract('/([a-z]*)', 1, content_type), duration_bucket=bin(req_duration_ms, 100)