(reg_num NUMBER(2) CONSTRAINT region_regnum_pk PRIMARY KEY,
             reg_name VARCHAR2(30) CONSTRAINT region_reg_name_nn NOT NULL);
             (class_num NUMBER(4) CONSTRAINT classification_classnum_pk PRIMARY KEY,
             class_type VARCHAR2(30) CONSTRAINT classification_classtype_nn NOT NULL);
             (cons_num NUMBER(8) CONSTRAINT consultant_consnum_pk PRIMARY KEY,
             reg_num NUMBER(2) CONSTRAINT consultant_reg_num_fk
             (cons_num NUMBER(8) CONSTRAINT expertise_cons_num_fk
             class_num NUMBER(4) CONSTRAINT expertise_class_num_fk
             REFERENCES classification(class_num),
             (org_num NUMBER(8) CONSTRAINT organization_org_num_pk PRIMARY KEY,
             reg_num NUMBER(2) CONSTRAINT organization_org_num_fk
             (client_num NUMBER(8) CONSTRAINT client_client_num_pk PRIMARY KEY,
             org_num NUMBER(8) CONSTRAINT client_org_num_fk
             reg_num NUMBER(2) CONSTRAINT client_reg_num_fk
             (contr_num NUMBER(10) CONSTRAINT contract_contr_num_pk PRIMARY KEY,
             contr_date DATE CONSTRAINT contract_contr_date_nn NOT NULL,
             client_num NUMBER(8) CONSTRAINT contract_client_num_fk
             class_num NUMBER(4) CONSTRAINT contract_class_num_fk
             REFERENCES classification(class_num),
             cons_num NUMBER(8) CONSTRAINT contract_cons_num_fk
             ...