Use the database field value expression to reference database
    fields in record selection expressions and in other value
    expressions.

1  –  Examples

    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.

1.1  –  C Example

    #include <stdio.h>
    DATABASE PERS = FILENAME "PERSONNEL";

    main()
    {
    READY PERS;
    START_TRANSACTION READ_ONLY;

    FOR J IN JOBS WITH J.JOB_CODE = "APGM"
       printf ("%s", J.JOB_TITLE);
       printf ("  $%f", J.MINIMUM_SALARY);
       printf ("  $%f\n", J.MAXIMUM_SALARY);
    END_FOR;

    COMMIT;
    FINISH;
    }

1.2  –  Pascal Example

    program fld_value (input,output);
    DATABASE PERS = FILENAME 'PERSONNEL';

    begin
    READY PERS;
    START_TRANSACTION READ_ONLY;

    FOR J IN JOBS WITH J.JOB_CODE = 'APGM'
       writeln (J.JOB_TITLE,
                ' $', J.MINIMUM_SALARY: 10 : 2,
                '  $', J.MAXIMUM_SALARY: 10 : 2);
    END_FOR;

    COMMIT;
    FINISH;
    end.

2  –  Format

  (B)0db-field-expr

    qqq> context-var qqq> . qqq> field-name qqq>

2.1  –  Format arguments

    context-var            A context variable. A temporary name that
                           you associate with a relation. You define
                           a context variable in a relation clause.
                           For more information see the entry on
                           Context Variables.

    field-name             The name of a field in a relation. For
                           example, once you have defined E as
                           the context variable for the EMPLOYEES
                           relation, E.LAST_NAME is a value
                           expression that refers to a value from
                           the LAST_NAME field of EMPLOYEES.