"Duilio Foschi" <dedalus@...> wrote in message
news:3.0.1.32.20020125210751.006c6430@......

> I have to verify that the touple (Y_MOV,N_MOV) of a slave table is
> contained in the master table.

alter table slave
add constraint ynmov foreign key(y_mov, n_mov)
references master(y_mov, n_mov)
[on delete <action>] [on update <action>];

(The last line above ONLY if you need cascade RI.)

It's time that you invest efforts reading LangRef, man. This is the same
command that Lucas Franzen gave you. Exactly the same, but with two columns.

C.
--
Claudio Valderrama C. - http://www.cvalde.com - http://www.firebirdSql.org
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