单项选择题
A.A check constraint on the EMPLOYEE table
B.A unique constraint on the EMPLOYEE table WORKDEPT column
C.A foreign key reference from the DEPARTMENT tables DEPTNO column to the WORKDEPT column of the EMPLOYEE table
D.A foreign key reference from the EMPLOYEE tables WORKDEPT column to the DEPTNO column of the DEPARTMENT table
单项选择题 Which of the following constraint types can be used to ensure the value of an INTEGER column references only positive values?（）
单项选择题 A view is created with the following statement:CREATE VIEW v1 AS SELECT col1, col2, col3 FROM t1 WHERE col4 > 1000 ; When will DB2 access the data from table T1 for view V1?（）
单项选择题 A table was created using the following DDL: CREATE TABLE employee (id SMALLINT NOT NULL, name VARCHAR(9), dept SMALLINT CHECK (dept BETWEEN 10 AND 100), job CHAR(10) CHECK (job IN (Sales,Mgr,Clerk)), hiredate DATE, salary DECIMAL(7,2), comm DECIMAL(7,2), PRIMARY KEY (id), CONSTRAINT yearsal CHECK (YEAR(hiredate) > 2004 OR salary > 80500) ); Which of the following INSERT statements will fail?（）