create table T(
field1 type not null,
field2 type,
field3 type,
constraint Pk_T primary key(field1,field2) ,
constraint FK_T FOREIGN KEY(field1)
)
create table T(
field1 type not null,
field2 type,
field3 type,
constraint Pk_T primary key(field1,field2) ,
constraint FK_T FOREIGN KEY(field1)
)