sql - Oracle - Having foreign keys in more than one table -

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i'm not sure if 1 can need have foreign key reference 2 tables.

table1 has 2 columns (a pk, b) table2 has 2 columns (c pk, d)

table3 has 3 columns (a pk, b pk, e) , made of first 2 table.

what hoping following:

create table table3      (   varchar2 (4),      c varchar2 (10),     e char (1),     constraint pk_a_c primary key (a, c),     constraint fk_a_c    foreign key (a, c)     references (table1.a, table2.b) );

i hope makes sort of sense.

thanks

james

a given foreign key constraint describes relationship 1 child table 1 parent table.

you can, however, have 2 foreign key constraints, each pointing respective table:

create table table3      (   varchar2 (4),      c varchar2 (10),     e char (1),     constraint pk_a_c primary key (a, c),     constraint fk_a      foreign key (a)       references table1(a),     constraint fk_b      foreign key (c)       references table2(b) );

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