单项选择题
A.SELECT * FROM t1 UNION SELECT * FROM t2
B.SELECT * FROM t1 UNION DISTINCT SELECT * FROM t2
C.SELECT * FROM t1 INTERSECT SELECT * FROM t2
D.SELECT * FROM t1 WHERE (c1,c2)= (SELECT c1,c2 FROM t2)
单项选择题 Which kind of non-sourced UDF can be created so that it only returns a single value?()
单项选择题 Given the following stored procedure:CREATE PROCEDURE increase_salary ( IN p_workdept CHAR(6), OUT p_sum DECIMAL(9,2) ) SET p_sum = (SELECT SUM(salary) FROM employee WHERE workdept=p_workdept);How can this stored procedure be called from the Command Line Processor?()
单项选择题 The opening of cursor CSR01 produces the following result set: STUDENT LASTNM FIRSTNM CLASSNO 123 Brown John T100 213 Bailey James T100 312 Carter Arlene T210 465 Chas Devon T305 546 Davis Steven T405 If this Fetch statement is executed: FETCH csr01 INTO :studnum, :firstname, :lastname, :class Which of the following DELETE statements will cause this row to be deleted?()