editing string using sed or grep

Question

first of all please execuse my ignorance on UNIX. I am quite new.

I have lot many sql files that contains following string

${DB_USERNAME}.${TABLE_NAME}

Can anyone please tell me how could I change it in each file so that it remains only

${TABLE_NAME}

I have tried following pattern of sed.

sed 's/^[^\.]\+\.//'

But it returns only ".".

Please tell me whole combination of grep and sed.

I need to change files directly. As I think we should pipe output of grep to sed. remember I am on AIX

Answer 1

Why so complicated? If you only want to remove the specific part:

sed 's/${DB_USERNAME}.//g' < input-file > output-file

If you want to go with something like your original expression:

sed 's/^[^\.]*\.//g' < input-file > output-file