php - MySQL LIKE 查询不提取相似数据

Question

我有一个简单的基于 MySQL 的搜索脚本，下面我将只发布与问题相关的部分。

$name = 'John Doe';
$query = 'SELECT username FROM members WHERE name LIKE %$name%';

现在，问题是当我搜索 John Doe 而不是获取具有该特定名称的用户时，我获取了所有名为 John 和 Doe< 的用户 而且，有趣的是，它甚至没有将 John Doe 放在顶部，这意味着......您可以在此之前找到 John xxxx。

是否有高级 MySQL 属性来完成此任务？

Answer 1

改变

$query = 'SELECT username FROM members WHERE name LIKE %$name%';

到

$query = 'SELECT username FROM members WHERE name LIKE "'.%$name%.'"';

或

$query = "SELECT username FROM members WHERE name LIKE '%$name%'";

请注意，更改为

$query = 'SELECT username FROM members WHERE name LIKE "%$name%"';

不会做这个把戏。

这是因为single quoted strings不要解释变量。

Note: Unlike the double-quoted and heredoc syntaxes, variables and escape sequences for special characters will not be expanded when they occur in single quoted strings.

Double quoted strings但是，会的。

The most important feature of double-quoted strings is the fact that variable names will be expanded. See string parsing for details.

更新:感谢 Memolition，这被大量编辑并改变了含义 :)