How to add data to the table if it is already there?

Question

PostgreSQL

I need to add data to a column, but there is already data in the column and I don’t need this data to go somewhere, but just a word was added next to it, how to do this I use a posgresql table

Answer 1

This is not how it works in RDBMS. You need to read the necessary data, save it somewhere (in a variable or file), perform the necessary operations (in this case, if I understand correctly, concatenate with a new line), and only then do an update that will change the old to the new.