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sql中,In和where的区别

<pre class="best-text mb-10"><span style="font-size: 16px; font-family: 宋体"><span class="baidu-highlight">sql 语句中In 和 Where 的含义不同。<span style="font-size: 16px; font-family: 宋体">应用解释如下:<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 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 style="font-size: 16px; font-family: 宋体">下面举例说明:<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 style="font-family: 宋体"><span style="font-size: 16px">Select from student where name in('A','B');<span style="font-size: 16px">.......................................................................................................................<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in 里面是个子查询或者给定的值比如 select from student where <a class="baidu-highlight" href="https://www.baidu.com/s?wd=Sn&amp;tn=44039180_cpr&amp;fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1Y3rAczuHnvPjuhryubnHub0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3EPHmdn1fvnHD" target="_blank">Sname='张三';/查询姓名叫张三的学生的信息/select from student where <a class="baidu-highlight" href="https://www.baidu.com/s?wd=Sn&amp;tn=44039180_cpr&amp;fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1Y3rAczuHnvPjuhryubnHub0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGCpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3EPHmdn1fvnHD" target="_blank">Sname in('张三','李四');/查询张三和李四的学生的信息/select from student where <a class="baidu-highlight" href="https://www.baidu.com/s?wd=Sn&amp;tn=44039180_cpr&amp;fenlei=mv6quAkxTZn0IZRqIHckPjm4nH00T1Y3rAczuHnvPjuhryubnHub0ZwV5Hcvrjm3rH6sPfKWUMw85HfYnjn4nH6sgvPsT6KdThsqpZwYTjCEQLGcpyw9Uz4Bmy-bIi4WUvYETgN-TLwGUv3EPHmdn1fvnHD" target="_blank">Sname in(select Sname from sn where Sno='001');/查询学号是001的学生信息/<span style="font-size: 16px">

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