Extracting string value before bracket using regexp in Athena

Question

I am trying to learn about regexp and I am trying to extract data that is before open bracket character using regexp_extract.

String value:

device
iphone-ios-cx 12.45.0(2144)

Expected output:

device
iphone-ios-cx 12.45.0

I am able to achieve this using split_part function.

select split_part(device, '(', 1)
FROM devices_tbl

I tried the same using regexp_replace and regexp_extract, both seem to give me incorrect results

select regexp_replace(device, '\\(.*\\)','')
FROM devices_tbl

How can I achieve the same using regex functions in Athena?

Answer 1

You got parenthesis escaping wrong, use single \:

select regexp_replace('iphone-ios-cx 12.45.0(2144)', '\(.*\)','');

Output:

         _col0         
-----------------------
 iphone-ios-cx 12.45.0