Referential integrity

I am having tow tables

CREATE TABLE A1(
Id CHAR(4),
FileName CHAR(X),
primary key(Id)
)

CREATE TABLE A2(
Id CHAR(4) ,
FileName VARCHAR(250),
primary key(Id)
)

Whenever i update Table A1 column "FileName" with X the same record, with same Id,in Table A2 automatically need to be deleted. I need to maintain Referential integrity between both tables.  

Can you please suggest a Modified table quries for the above

Thanks in advance Received on Thu May 23 2002 - 12:52:00 CEST