如何获取ResultSet的整数值并将其赋值给int变量？

Question

int bookID返回值0，它应返回1。 （表格中的第一个ID。）请帮助。

public void ID(){

   conn = ConnectDB();

   String sql = "Select Book_ID From Student Biblio";
   try {
       pst = conn.prepareStatement(sql);
       rs = pst.executeQuery();

       if(rs.next()){
        int bookID = rs.getInt(1); //IDTable


       }

   } catch (SQLException ex) {
       Logger.getLogger(Student.class.getName()).log(Level.SEVERE, null, ex);
   }
}

Answer 1

而不是尝试使用while循环并检查表的行。

Answer 2

试试这可能会帮助你

public void ID(){

   conn = ConnectDB();

   String sql = "Select Book_ID From Student Biblio";
   try {
       pst = conn.prepareStatement(sql);
       rs = pst.executeQuery();

       while(rs.next()){
        int bookID = rs.getInt("Book_ID"); //IDTable


       }

   } catch (SQLException ex) {
       Logger.getLogger(Student.class.getName()).log(Level.SEVERE, null, ex);
   }
}