一些SQL--过滤数据

Server version: 5.6.47 MySQL Community Server (GPL)

1.使用WHERE子句
SELECT prod_name,prod_price FROM Products WHERE prod_price=3.49;

2.检查单个值
SELECT prod_name,prod_price FROM Products WHERE prod_price<10;

SELECT prod_name,prod_price FROM Products WHERE prod_price<=10;

3.不匹配检查
SELECT vend_id,prod_name FROM Products WHERE vend_id<>'DLL01';

SELECT vend_id,prod_name FROM Products WHERE vend_id!='DLL01';

4.范围值检查
SELECT prod_name,prod_price FROM Products WHERE prod_price BETWEEN 5 AND 10;

5.空值检查
SELECT prod_name FROM Products WHERE prod_price IS NULL;

SELECT cust_name FROM Customers WHERE cust_email IS NULL;