sql_execute.java

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package ksnb;

import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.Connection;

public class SQL_execute {

    private Statement st;
    private ResultSet rs;
    private Connection con;
    SQL_odbc db;

public SQL_execute() {

    db=new  SQL_odbc();
    try{
        con=db.connect();    //接收user_odbc中connect的返回值
        st=con.createStatement();
    }
    catch(Exception e)
    {
        System.out.println("连接数据库出现错误");
    }
}
public int update(String sql) throws Exception {
    int x=0;
    try
    {
        x=st.executeUpdate(sql);
        System.out.println("更新数据成功");
    }
    catch (Exception e)
    {
        System.out.println("数据更新失败，出现异常："+e.toString());
        System.out.println("失败原因是："+e.toString());
    }
  //关闭数据库
    return x;

}

   public ResultSet query(String sql)
       {
           try
           {
               rs = st.executeQuery(sql);
           }catch(Exception e)     {              System.out.println(e.toString());           }

           return rs;

    }
    public  boolean close()  //关闭数据库
   {
       boolean bl;
       try{
           db.close();
           bl=true;
       }
       catch(Exception e){ bl=false;}
       return bl;
   }

}