单项选择题
Given that tables T1 and T2 contain the following rows:
Table T1: C1 C2 1 4 1 3 1 2
Table T2: C1 C2 1 1 1 2 1 3
Which of the following queries will return only those rows that exist in both T1 and T2?()
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)
相关考题
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单项选择题
Which kind of non-sourced UDF can be created so that it only returns a single value?()
A.Row
B.Table
C.Scalar
D.Column -
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?()
A.CALL increase_salary('A00')
B.VALUES increase_salary('A00')
C.CALL increase_salary('A00', ?)
D.VALUES increase_salary('A00', ?) -
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?()
A.DELETE ALL FROM tab01 FOR CURRENT OF csr01
B.DELETE FROM tab01 FOR CURRENT csr01 WITH RS
C.DELETE * FROM tab01 WHERE CURRENT csr01 WITH CS
D.DELETE FROM tab01 WHERE CURRENT OF csr01 WITH RR
