Loop for's result in a variable for sql query

I have this part of my script

for i in  `cat ${RELLIST}`
do
  for mr in  `cat ${i}/DBA/install.list`
  do
     grep -i "'dba_" ${i}/DBA/sql/${mr}/*.tab 2> /dev/null | sed 's/^.*://'
     #grep -i supp_mr_audit ${i}/DBA/sql/${mr}/*.tab 2> /dev/null
  done
done

I mean that i need to move the result of the script in this query

select * from tables where table_name in (TABLIST)

After this step i need to run the complete query into the db that i called before in the command's run with the name of the script.

I'm new with scripting and i don't know how to create this variable to insert in a sql command.