Добрый вечер. При создании БД ошибка. В чем проблема?

автор
CREATE DATABASE 'C:\BD\PRACT5.GDB' USER 'SYSDBA' PASSWORD 'masterkey';
commit;

CREATE TABLE region (
RegId INTEGER NOT NULL PRIMARY KEY,
RegName VARCHAR(128)
);
commit;

CREATE TABLE class (
ClassId INTEGER NOT NULL PRIMARY KEY,
ClassName VARCHAR(128)
);
commit;

CREATE TABLE crime (
CrimeId INTEGER NOT NULL PRIMARY KEY,
ClassId INTEGER,
CrimeName VARCHAR(128),
FOREIGN KEY (ClassId) REFERENCES class (ClassId)
);
commit;

CREATE TABLE infa (
CrimeId INTEGER,
RegId INTEGER,
Yeaar INTEGER,
AccQuant INTEGER,
UncQuant INTEGER,
FOREIGN KEY (CrimeId) REFERENCES class (CrimeId),
FOREIGN KEY (RegId) REFERENCES region (RegId)
);



Ошибка.

автор
Unsuccessful metadata update
could not find UNIQUE INDEX with specified columns
Statement: CREATE TABLE infa (
CrimeId INTEGER,
RegId INTEGER,
Yeaar INTEGER,
AccQuant INTEGER,
UncQuant INTEGER,
FOREIGN KEY (CrimeId) REFERENCES class (CrimeId),
FOREIGN KEY (RegId) REFERENCES region (RegId)
)

Таблоид,

Большое спасибо!