1.使用WHERE子句
WHERE子句需要在FROM子句之后给出
注意，应该让order b子句位于where子句之后，否则会产生错误。
2.where子句操作符
mysql> select prod_name,prod_price from products where prod_name = ‘fuses‘; mysql> select prod_id,prod_price from products where prod_id = 1003; mysql> select prod_name,prod_price from products where prod_price between 5 and 10; mysql> select cust_id from customers where cust_email is null;
原文：https://www.cnblogs.com/FQQa/p/13139855.html