The following programs demonstrate the use of the database field
    value expression. These programs use the database field value
    expression, FOR J IN JOBS, to declare the context variable J.
    This allows the programs to use the clause, J.JOB_CODE, to mean
    JOBS.JOB_CODE. The programs search the field JOB_CODE for the
    string "APGM". Any record that contains the specified string
    becomes part of the record stream. These programs then use J to
    qualify the fields in the host language print statements. The job
    title, minimum salary and the maximum salary for each record in
    the record stream are printed.