ocp题库解析：11g-1Z0-051-第14题
ocp题库解析：11g-1Z0-051-第14题，完整题库请点击这里联系老师咨询了解
14. Using the CUSTOMERS table, you need to generate a report that shows 50% of each credit
amount in each income level. The report should NOT show any repeated credit amounts in each income
level. --each income level中没有重复的credit amounts
Which query would give the required result?
A.
SELECT cust_income_level, DISTINCT cust_credit_limit * 0.50
AS "50% Credit Limit"
FROM customers;
[sql] view plain copy print?
sh@TESTDB> SELECT cust_income_level, DISTINCT cust_credit_limit * 0.50
2 AS "50% Credit Limit"
3 FROM customers;
SELECT cust_income_level, DISTINCT cust_credit_limit * 0.50
*
ERROR at line 1:
ORA-00936: missing expression
语法错误，DISTINCT不应该放在第二列，应该放在第一列中
[sql] view plain copy print?
sh@TESTDB> SELECT DISTINCT cust_income_level,cust_credit_limit * 0.50
2 AS "50% Credit Limit"
3 FROM customers where rownum<6;
CUST_INCOME_LEVEL 50% Credit Limit
------------------------------ ----------------
G: 130,000 - 149,999 5500
G: 130,000 - 149,999 4500
G: 130,000 - 149,999 3500
G: 130,000 - 149,999 750
B.
SELECT DISTINCT cust_income_level, DISTINCT cust_credit_limit * 0.50
AS "50% Credit Limit"
FROM customers;
同A，语法错误，DISTINCT不应该放在第二个
[sql] view plain copy print?
SELECT DISTINCT cust_income_level, DISTINCT cust_credit_limit * 0.50
2 AS "50% Credit Limit"
3 FROM customers;
SELECT DISTINCT cust_income_level, DISTINCT cust_credit_limit * 0.50
*
ERROR at line 1:
ORA-00936: missing expression
C.
SELECT DISTINCT cust_income_level ' ' cust_credit_limit * 0.50
AS "50% Credit Limit"
FROM customers;
[sql] view plain copy print?
sh@TESTDB> SELECT DISTINCT cust_income_level ' ' cust_credit_limit * 0.50
2 AS "50% Credit Limit"
3 FROM customers;
SELECT DISTINCT cust_income_level ' ' cust_credit_limit * 0.50
*
ERROR at line 1:
ORA-00923: FROM keyword not found where expected
这道题愿意为用' '连接两个列，可能用错，应为||来连接，不过DISTINCT的位置 对的
[sql] view plain copy print?
sh@TESTDB> SELECT DISTINCT cust_income_level || cust_credit_limit * 0.50
2 AS "50% Credit Limit"
3 FROM customers where rownum<6;
50% Credit Limit
----------------------------------------------------------------------
G: 130,000 - 149,999750
G: 130,000 - 149,9994500
G: 130,000 - 149,9993500
G: 130,000 - 149,9995500
D.
SELECT cust_income_level ' ' cust_credit_limit * 0.50 AS "50% Credit Limit"
FROM customers
D没有满足NOT show any repeated的条件。
此题答案C
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