单项选择题
A.INSERT INTO tab1 SELECT cx, cy FROM tab2
B.INSERT INTO tab1 VALUES (tab2.cx, tab2.cy)
C.INSERT INTO tab1 VALUES (SELECT cx, cy FROM tab2)
D.INSERT INTO tab1 (c1, c2) VALUES (SELECT cx, cy FROM tab2)
单项选择题 Given that tables T1 and T2 contain the following rows: Table T1: C1 C2 5 4 5 2 5 5 Table T2: C1 C2 5 1 5 2 5 3 Which of the following queries will return only those rows that exist in T1 and not in T2?（）
单项选择题 How should the following UDF be invoked in order to convert US currency values stored in the EXPENSES table into Canadian currency?CREATE FUNCTION getratews11 ( country1 VARCHAR(100), country2 VARCHAR(100) ) RETURNS DOUBLE LANGUAGE SQL CONTAINS SQL EXTERNAL ACTION NOT DETERMINISTIC BEGIN ... END（）
单项选择题 Given the following tables: CONTINENTS ID NAME COUNTRIES 1 Antarctica 0 2 Africa 53 3 Asia 47 4 Australia 14 5 Europe 43 6 North America 23 7 South America 12 REGION ID LOCATION 1 East 2 West How many rows would be returned using the following statement? SELECT location FROM continents, region（）