java - MySQL Java根据两个字符串列删除行

Question

这是一行

PreparedStatement delete = con.prepareStatement("DELETE FROM " + tableName +" WHERE first LIKE " + firstName + " AND last LIKE " + lastName);

我想在删除行之前检查名字和姓氏是否与查询匹配。“第一个”和“最后一个”都是我表中的列。我收到此错误消息

org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (no such column: Hendrix)

在本例中，Hendrix 是 lastName 的值。

为什么最后一个 LIKE ____ 在这种情况下不起作用？如果我要检查，是否应该使用另一个关键字多个字符串？

Answer 1

In Java, you can escape quotes with \ :

PreparedStatement delete = con.prepareStatement("DELETE FROM " + tableName + " WHERE first = \"" + firstName + "\" AND last = \"" + lastName + "\"");

当然，我发现有点难以阅读，所以我更喜欢混合使用单引号和双引号而不是转义它们:

PreparedStatement delete = con.prepareStatement('DELETE FROM ' + tableName + ' WHERE first = "' + firstName + '" AND last = "' + lastName + '"');

关于你关于LIKE的问题。 Try reading up on the difference between LIKE and = 。有很多关于它的信息。简而言之...LIKE 与通配符一起使用。