The difference between In and Where in SQL statements

<span style="font-size: 16px; font-family: 宋体"><span class="baidu-highlight">SQL</span> 语句中In 和 Where 的含义不同。</span><br/><span style="font-size: 16px; font-family: 宋体">应用解释如下：</span><br/><br/><span style="font-size: 16px; font-family: 宋体">1、如需有条件地从表中选取、删除、更新数据时，使用Where；</span><br/><span style="font-size: 16px; font-family: 宋体">2、In只作为Where条件子句下的一个运算符，除了In之外还有Between、Like、=、>、>=、<、<=等运算符。</span><br/><span style="font-size: 16px; font-family: 宋体">下面举例说明：</span><br/><span style="font-size: 16px; font-family: 宋体">1、查询名字为A和B的学生，则语句为</span><br/><span style="font-family: 宋体"><span style="font-size: 16px">Select * from student where name in(&#39;A&#39;,&#39;B&#39;);</span><span style="font-size: 16px"><br/>.......................................................................................................................<br/></span><span style="font-size: 16px"><span class="con">where 后面是一个条件式，表示要找出满足这个条件的结果<br/>in 里面是个子查询或者给定的值<br/>比如 select * from student where Sname=&#39;张三&#39;；/*查询姓名叫张三的学生的信息*/<br/><br/>select * from student where Sname in(&#39;张三&#39;,&#39;李四&#39;)；/*查询张三和李四的学生的信息*/<br/><br/>select * from student where Sname in(select Sname from sn where Sno=&#39;001&#39;)；/*查询学号是001的学生信息*/</span></span><span style="font-size: 16px"><br/></span></span>