java - 通过搜索两列从数据库返回数据

Question

当用户输入与 cUsername 和 cPassword 匹配时，我希望显示所有字段。对此进行测试时，我的 SQL 语法出现错误(靠近 cPassword 之类的位置)。有人可以提出这个问题吗？请注意我还没有经历过 SQL 注入(inject)...

public Car getLogin(String searchUser, String searchPass) {
    Car foundCar1 = new Car();
    try {
        Class.forName("com.mysql.jdbc.Driver");
        Connection conn = DriverManager.getConnection(url + dbName, userName, password);
        statement = conn.createStatement();
        resultSet = statement.executeQuery("select * from eflow.registration where cUsername like '" + searchUser
                + "' AND where cPassword like '" + searchPass + "'");

        while (resultSet.next()) {
            foundCar1 = new Car(resultSet.getInt("cID"), resultSet.getString("cLicense"),
                    resultSet.getInt("cJourneys"), resultSet.getString("cUsername"),
                    resultSet.getString("cPassword").toString());
        }
        conn.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return foundCar1;
}

Answer 1

除了您的错误之外，这里还有一些有问题的事情。该错误是由多个where 子句引起的。通过更改来修复此问题:

AND 其中 cPassword like 到 AND cPassword like

我看到的另一件事是 like 应该与通配符结合使用，因此您可能需要更改:

resultSet = statement.executeQuery("select * from eflow.registration where cUsername like '" + searchUser
            + "' AND where cPassword like '" + searchPass + "'");

至:

resultSet = statement.executeQuery("select * from eflow.registration where cUsername like '%" + searchUser
            + "%' AND cPassword like '%" + searchPass + "%'");

除非您正在寻找完全匹配，在这种情况下我会删除 like 并使用“=”代替。