managesql.java

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package ksnb;
import java.sql.*;
import java.util.*;
import ksnb.conn;
public class ManageSql {

    Statement st;
    ResultSet rs;
    public conn c;
    public Connection con;
    public ManageSql() {
        try
        {
            c=new conn();
            con=c.getConncetion();
        }
        catch(Exception e)
        {

        }
    }
    //插入新管理员的信息
    public int Insert_Manage(String s)
    {
        int i=-1;
        try
        {

            st=con.createStatement();
            i=st.executeUpdate(s);
        }
        catch(Exception e)
        {
            System.out.println(s.toCharArray());
        }
        return i;
    }
    public int  queryuser(String user)    //用于查询表中是否是已存在输入的管理员名
    {
      int num=0;
      String sql="select count(*) as ct from Shop_Admin where Name='" +user + "'" ;  //查询数据库中的记录行数

      try{

          st=con.createStatement();
          ResultSet a=st.executeQuery(sql);
          if(a.next())
          {
              num = a.getInt("ct");  //提取记录中返回的行数
          }
      }
      catch(Exception e)
      {
          System.out.println(e.getMessage());
      }
      return num;

    }
    //删除指定的管理员信息
    public int Delete_Manage(String s)
   {
       int i=-1;
       try
       {

           st=con.createStatement();
           i=st.executeUpdate(s);
       }
       catch(Exception e)
       {
           System.out.println(e.toString());
       }
       return i;
   }
   //修改指定的管理员的信息
   public int Update_Manage(String s)
   {
       int num=0;
       try
       {

           st=con.createStatement();
           num=st.executeUpdate(s);
       }
       catch(Exception e)
       {
           System.out.println(e.toString());
       }
       return num;
   }

//查询管理员的信息
   public ResultSet Query_Manage(String sql)
   {
       try
       {


           st=con.createStatement();
           rs=st.executeQuery(sql);
       }
       catch(Exception e)
       {
           System.out.println(e.toString());
       }
       return rs;

   }

}