2、(4-7) choose the best answer:
You need to display the first names of all customers from the CUSTOMERS table that contain the
character ‘e‘ and have the character ‘a‘ in the second last position.
Which query would give the required output?
A) SELECT cust_first_name
FROM customers
WHERE INSTR(cust_first_name, ‘e‘)<>‘‘ AND
SUBSTR(cust_first_name, -2, 1)=‘a‘;
B) SELECT cust_first_name
FROM customers
WHERE INSTR(cust_first_name, ‘e‘)<>0 AND
SUBSTR(cust_first_name, -2, 1)=‘a‘;
C) SELECT cust_first_name
FROM customers
WHERE INSTR(cust_first_name, ‘e‘)<>0 AND
SUBSTR(cust_first_name, LENGTH(cust_first_name),-2)=‘a‘;
D) SELECT cust_first_name
FROM customers
WHERE INSTR(cust_first_name, ‘e‘)IS NOT NULL AND
SUBSTR(cust_first_name, 1,-2)=‘a‘;
Answer:B
原文地址：http://blog.51cto.com/13854012/2349482