Removing question marks in front of records in QGIS

Question

I am using QGIS 3.10.3 and noticed some question marks in one column of the attribute table. These marks are just before the numbers and represent the currency symbol.

I want to get rid of them. I tried in the open Field Calculator this code: substr("fieldname", length("fieldname")-1). It deleted the question marks and the first numbers. How can I just delete the question mark?

Answer 1

Use this expression with the replace() function:

replace("fieldname", '?', '')

Answer 2

You can use a substring, based on regular expressions with regexp_substr() to output all charcters of the input except ? with this expression:

regexp_substr ("input",'([^\\?]+)')