大家好！我是黄啊码，上节课我们将了DISTINCT、 FROM 、 GROUP BY、 HAVING 、 ORDER BY 这些筛选数据的技能，是不是总感觉少了些啥？
你：啊码，你把最重要的where给漏了！
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好了，进入正题吧：WHERE 子句，说起来 SQL 其实很简单，只要能把满足条件的内容筛选出来即可，但在实际使用过程中，不同人写出来的 WHERE 子句存在很大差别，比如执行效率的高低，有没有遇到莫名的报错等。
这是今天的
目录
学会使用 WHERE 子句，如何使用比较运算符对字段的数值进行比较筛选；
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[TencentCloudSDKException] code:FailedOperation.ServiceIsolate message:service is stopped due to arrears, please recharge your account in Tencent Cloud requestId:c57cbbdc-5480-46b3-af34-651124e2e1ca
学会使用 WHERE 子句，如何使用比较运算符对字段的数值进行比较筛选；
比较运算符
在 SQL 中，我们可以使用 WHERE 子句对条件进行筛选，在此之前，你需要了解 WHERE 子句中的比较运算符。这些比较运算符的含义你可以参见下面这张表格：
啊码贴出的这图只是常用数据库的运算符，建议别直接copy就用。
你：为啥?作为老师，不应该是直接给准确答案吗？
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你：我只见过》答：略。
黄啊码：。。。
注：你需要查看使用的 DBMS 是否支持，不同的 DBMS 支持的运算符可能是不同的，比如 Access 不支持（!=），不等于应该使用（<>）。在 MySQL 中，不支持（!>）（!
Original: https://www.cnblogs.com/huangama/p/16506728.html
Author: 黄啊码
Title: 【黄啊码】MySQL入门—6、掌握这些数据筛选技能比你学python还有用-2
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