java - 如何更改PreparedStatement中from子句的表名

Question

嗨，我有一个小问题，我如何切换表来获取结果？下面的代码不起作用。但是，这应该让您了解我正在尝试做什么。感谢您的帮助

String typelogin=null;
if(xx){
   typelogin="users_table";
}else{
   typelogin="admin_table";
}
String sqlStr = "Select * from "+typelogin+" where username=? and userpassword=?";
PreparedStatement stmt = conn.prepareStatement(sqlStr);

完整代码:

Statement stmt = conn.createStatement();

            String sqlStr = "Select * from "+typelogin+" where username=? and userpassword=?";


            PreparedStatement pstmt=conn.prepareStatement(sqlStr);
            pstmt.setString(1,user);
            pstmt.setString(2,password);
            //step 6 Process result
            ResultSet rs = pstmt.executeQuery();

我收到的错误:

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'fromspmovy_admin where username='abc' and userpassword='abc'' at line 1

回答[已解决]:

忘记加空格

from " + typelogin + " where

Answer 1

从您的错误消息来看:'fromspmovy_admin where ... 看起来您错过了 from 和表名称之间的空格。确保您在所有方法中都以正确的方式执行此操作(请注意，在当前的示例中，这种情况不会发生)。