increment column value if key already exists

[simone1975]

I am trying to build an app sheet that uses EAN barcode as keys and then has a "Count" column.

the goal is to have a sheet with a row for each EAB scanned and a column "Count" that adds 1 at every scan.

so if you can a code once, you have 1 in that column, but if you happen to scan a code two times, then it should just update the "Count" value adding a +1

right now I am stuck at being able to catch the error: "There is already a row with the key 97888456465"

any help more than welcome!

[Steve · Accepted solution]

A solution is present in these search results.

[simone1975]

Steve thanks for the pointer, but I have not find much help in those solutions...