пишет ошибку на 4 таблице prodaja Msg 1778, Level 16, State 0, Line 1 Column 'prodavci.kod_prodavca_id' is not the same data type as referenc

create table prodaja_kompov(
tovari_id integer identity (1,1) not null primary key,
naimenovanie_tovara varchar(20) not null,
osnovnie_harakteristiki varchar(100) not null,
stoimost integer not null,
garantita integer not null,
kolichestvo integer not null,
);
 
create table prodavci
(kod_prodavca_id int not null,
FIO varchar(20) not null,
adres varchar(20) not null,
data_rojdeniya datetime not null,
telefon integer not null,
primary key (kod_prodavca_id));
 
 
 
create table pokupateli
(kod_pokupatelya_id int not null,
FIO varchar(20) not null,
telefon varchar(10) not null,
adres varchar(20) not null,
primary key (kod_pokupatelya_id));
 
 
create table prodaja
(tovar_id int not null FOREIGN KEY REFERENCES prodaja(tovar_id)
kolichestvo integer not null,
cena integer not null,
data integer not null,
prodavec varchar(20) not null FOREIGN KEY REFERENCES prodavci(prodavca_ID),
pokupatel varchar (20) not null FOREIGN KEY REFERENCES pokupateli(pokupatelya_ID)
primary key (tovar_id));