very long string variable?

Question

Is there a longer type variable for building lengthy sql statements? how add new line too? I want to store the statement in a very long variable text so I can run it from sql prompt. I think it will exceed limit if I use normal variable. thanks

    export DATABASE_LIST="/location/dblist.cfg"
    export SQL_INSERT_TEXT=""

    while read -r USERID ORACLE_SID2
    do

    ### how do I do this if too long?? and add new line
    SQL_INSERT_TEXT="${SQL_INSERT_TEXT} longgSqlStatements; \newline"

    done < <(tac $DATABASE_LIST)

    echo ${SQL_INSERT_TEXT}


    export sqllog = "/location/sqllog.log"
    $ORACLE_HOME/bin/sqlplus -S accnt_name@db_name << EOF >${sqllog}
    ${SQL_INSERT_TEXT}
    EOF

Answer 1

Linux shells generally don't have any variable types. There are just strings, and the maximum length of a string can be had by running getconf ARG_MAX; on my system the maximum string is about 2M chars long.

Try using bash's builtin printf -v to conveniently load a variable with new lines, like this:

printf -v s "%s\n" hello there, this works "with quotes" too\.
echo "$s"

Output:

hello
there,
this
works
with quotes
too.

So the syntax might be something like:

printf -v SQL_INSERT_TEXT '%s\n' "${SQL_INSERT_TEXT}" "longgSqlStatements;"

Or, depending on what's needed, perhaps:

printf -v SQL_INSERT_TEXT '%s\n' "${SQL_INSERT_TEXT} longgSqlStatements;"