Mike, the following is from IMAGE/SQL's display map:
 
INVOICES (INVOICES)
    INVOICE-NO           INVOICE_NO      J4       CHAR(20)        I
 
As you say, the J4 maps to a CHAR(20) and is Imprecise/Incompatible.
 
I don't want ANY items, defined as J4, to be mapped to CHAR(20). So you can
do the following, in IMAGE/SQL:
 
     UPDATE TYPE J4 IN * TO DECIMAL(15,0)
 
Now, a DI MAP <setname> displays:
 
INVOICES (INVOICES)
     INVOICE-NO           INVOICE_NO     J4       DECIMAL(15,0)    IU
 
Hope this is of some help.
Best regards,
Steve Patrick
HP Database Expert Center