Checking duplicates and positive number

1. Form

2.

declare

    chk_button number;

    xcount number;

begin

   

    --checking duplicates

    select count(*) into xcount from suplr_mstr where suplr_mstr.suplrid=:suplr_mstr.supLrid;

   

    if xcount <>0 then

        message('Enter supplier''s identity number');

        set_alert_property ('IO_ALERT', title, 'Primary Key Violation');

        set_alert_property ('IO_ALERT', alert_message_text, 'Supplier''s ID number already exist');

        chk_button:=show_alert('IO_ALERT');

        RAISE FORM_TRIGGER_FAILURE;

    END IF;

--checking filed if not greater than zero

   

    if not:suplr_mstr.supLrid>0 then

      message('Enter supplier''s identity number');

        set_alert_property ('BUSS_ALERT', title, 'Business Rule Violation');

        set_alert_property ('BUSS_ALERT', alert_message_text, 'Supplier''s ID should be positive integer');

        chk_button:=show_alert('BUSS_ALERT');

        RAISE FORM_TRIGGER_FAILURE;

    END IF;

END;

3. Output