将PHP PDO查询写为`dbName`.`tableName`而不是`tableName`-为什么?

本文介绍了将PHP PDO查询写为`dbName`.`tableName`而不是`tableName`-为什么?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 我正在用PHP PDO编写用户注册函数，并且发现我的查询只有在这样写的情况下才能正常运行:I'm writing a user registration function in PHP PDO, and I have found that my query will only run fine if it is written like this:<?php $dbHost="localhost"; $dbName="project"; $dbUser="admin"; $dbPassword="abcd"; $dbh=new PDO("mysql:host=$dbHost;dbName=$dbName", $dbUser, $dbPassword); $dbh->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); $query=$dbh->prepare("INSERT INTO project.users (userName, userEmail) VALUES (?,?)");.....另一方面，如果我这样写，它将无法运行:On the other hand, it will not run if I write:...$query=$dbh->prepare("INSERT INTO users (userName, userEmail) VALUES (?,?)");...在这种情况下，我收到以下错误消息:In that case, I get the following error message: 为什么我需要精确project.users?既然数据库名称本身已经在PDO对象中，为什么输入表名称还不够?Why is it that I need to precise project.users? Why isn't it enough to enter the table name, given that the db name itself is already in the PDO object?谢谢！ JDelage 更新，请参阅下面的接受的答案.用dbname=$dbName替换dbName=$dbName可解决此问题.UPDATE Please see accepted answer below. Replacing dbName=$dbName with dbname=$dbName solves this problem.推荐答案显然，PDO无法将活动数据库设置为项目"，因此您需要每次都指定它.Apparently PDO was unable to set active database to be "project" and therefore you need to specify it every time.尝试修改您的行，使其看起来像这样:Try to modify your line to look like this:$dbh=new PDO("mysql:host=$dbHost;dbname=$dbName", $dbUser, $dbPassword);唯一的区别是dbname拼写为小写而不是您的dbName. The only difference is that dbname is spelled all lower-case instead of yours dbName. 或者，在成功建立连接后执行以下SQL命令:USE project;，例如Alternatively, execute this SQL command after successfully establishing a connection:USE project;, e.g.$dbh->exec('USE project;'); 这篇关于将PHP PDO查询写为`dbName`.`tableName`而不是`tableName`-为什么?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！