如何解决MySQLSyntaxErrorException异常？

Question

当我创建update jsp mysql时，我不断收到MySQLSyntaxErrorException。

String id_user = request.getParameter("id_login");    
String name_cust = request.getParameter("name_cust");
String password = request.getParameter("password");
String email = request.getParameter("email");
String no_phone = request.getParameter("no_phone");


Statement st = CON.createStatement();
//ResultSet rs;
int i = st.executeUpdate("UPDATE signup SET id_login='"+id_user+"',name_cust='"+name_cust+"', password='"+password+"'email='"+email+"',no_phone='"+no_phone+"', WHERE id_user='"+id_user+"'");

Answer 1

您在,之前有额外的WHERE，而您在EMAIL之前错过了一个"UPDATE signup SET id_login=?, name_cust=?, password=?, email=?, no_phone=? WHERE id_user=?" 。

PreparedStatement

此外，您应该使用 char original[5]; scanf("%5s", original); // String containing 5 chars ，以避免任何SQL注入。

Answer 2

SQL语句中的语法不正确，请尝试此

int i = st.executeUpdate("UPDATE signup SET id_login='"+id_user+"',name_cust='"+name_cust+"', password='"+password+"'email='"+email+"',no_phone='"+no_phone+"'WHERE id_user='"+id_user+"'");