55.Evaluate the following two queries:
来源:互联网 发布:转移概率矩阵计算方法 编辑:程序博客网 时间:2024/05/29 06:42
55.Evaluate the following two queries:
SQL> SELECT cust_last_name, cust_city FROM customers
WHERE cust_credit_limit IN (1000, 2000, 3000);
SQL> SELECT cust_last_name, cust_city FROM customers
WHERE cust_credit_limit = 1000 OR cust_credit_limit = 2000 OR cust_credit_limit = 3000;
Which statement is true regarding the above two queries?
A.Performance would improve in query 2.
B.Performance would degrade in query 2.
C.There would be no change in performance.
D.Performance would improve in query 2 only if there are null values in the CUST_CREDIT_LIMIT column.
答案:C
SQL> SELECT cust_last_name, cust_city FROM customers
WHERE cust_credit_limit IN (1000, 2000, 3000);
SQL> SELECT cust_last_name, cust_city FROM customers
WHERE cust_credit_limit = 1000 OR cust_credit_limit = 2000 OR cust_credit_limit = 3000;
Which statement is true regarding the above two queries?
A.Performance would improve in query 2.
B.Performance would degrade in query 2.
C.There would be no change in performance.
D.Performance would improve in query 2 only if there are null values in the CUST_CREDIT_LIMIT column.
答案:C
0 0
- 55.Evaluate the following two queries:
- 55.Evaluate the following two queries:
- 19.Evaluate the following query:
- 78.Evaluate the following query:
- 30.Evaluate the following CREATE TABLE commands:
- 31.Evaluate the following SQL commands:
- 43.Evaluate the following CREATE SEQUENCE statement:
- 146.Evaluate the following SQL statement:
- 155.Evaluate the following SQL statement
- 156.Evaluate the following SQL statement:
- 167.Evaluate the following DELETE statement:
- 作业笔记:How to evaluate the two-class classification model?
- ocp 047-141 Evaluate the following SQL statement:SELECT product_name || 'it's not available for orde
- ocp 047-92 Evaluate the following expression using meta. character for regular expression:'[^Ale|ax
- 16.Evaluate the following query: SQL> SELECT promo_name||q'{'s start date was }'||promo_begin_date A
- 39.Evaluate the following command:CREATE TABLE employees(employee_id NUMBER(2) PRIMARY KEY
- Following the pipeline
- The following tips could help
- 盘点:55个最实用大数据可视化分析工具
- Http请求保存用户的的登录状态
- 设计模式系列:状态模式
- 03 配置服务
- Spring事务配置的五种方式
- 55.Evaluate the following two queries:
- 九度-题目1070:今年的第几天?
- 设计模式系列:解释器模式
- mysql组内排序
- Android组件——使用DrawerLayout仿网易新闻v4.4侧滑菜单
- 关于eof和scanf返回值
- RabbitMQ的安装及配置
- 数据中心(IDC)基础设施如何适应未来IT需求变化的要求
- HTML中各标签属性