回答:谢谢邀请。可能还有:where 1= 0 where 11...小结:像这种写法，一般用于拼接 SQL语句的用法中，不管是 ORACLE, 还是 SQL SERVER，都支持这种特殊的写法。希望能对你有所帮助，谢谢。（结束）
khs1994
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458人阅读
回答:可以的，想知道会不会用到索引直接在语句前加上explain 关键字执行下就知道了，我有发布过关于怎么建索引的文章你可以查看下就清楚了
NicolasHe
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872人阅读
问题描述:[udp-717] ERROR cn.ucloud.udp.async.task.AbstractTask - 2022-11-15 15:56:00 [AsyncTask] java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing ...
303187999
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1675人阅读
Media Queries: How to target desktop, tablet and mobile? /* Media Queries: How to target desktop, tablet and mobile? http://webdesignerwall.com/tutorials/css3-media-queries https://stackoverflow...
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...： 假设一高频查询如下 SELECT * FROM user WHERE area=amoy AND sex=0 ORDER BY last_login DESC limit 30; 如何建立索引？描述考虑的过程 user表如下： 初始化100W条数据，其中，area要通过IP查询生成，sex为 0,1 随机 CREATE TABLE user (id int(10...
...： 假设一高频查询如下 SELECT * FROM user WHERE area=amoy AND sex=0 ORDER BY last_login DESC limit 30; 如何建立索引？描述考虑的过程 user表如下： 初始化100W条数据，其中，area要通过IP查询生成，sex为 0,1 随机 CREATE TABLE user (id int(10...
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... class of mathematical optimization problems, which includes least-squares and linear programming problems. It is well known that least-squares and linear programming problems have a fairly complet...
轻量云主机已更新简化版Windows帕鲁镜像的安装教程，现在仅需3步，就可以畅游帕鲁大陆！需要Lin...
UCloud轻量云主机已更新Linux帕鲁镜像的安装教程，现在仅需1步，就可以畅游帕鲁大陆！也欢迎大...
