package day03;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;

import day01.JdbcUtil;

/*
 * 演示：JDBC的批量處理
 */

public class Demo3 {
    public static void main(String[] args) {
//      testInsert();
        int[] empNos=new int[30];
        int empNo=1209;
        for(int i =0;i<empNos.length;i++){
            empNos[i]=empNo;
            empNo-=5;
        }
        deleteByEmpNos(empNos);
    }
    //批量插入
    public static void testInsert(){
        Connection conn=null;
        Statement st=null;
        try {
            conn=JdbcUtil.getConnection();
            st=conn.createStatement();
            int count =1290;
            for(int i=0;i<=count;i++){
                String sql="insert into emp(empno,ename) values(empseq.nextval,'員工"+i+"')";
                //添加sql語句到語句對象的語句列表中
                st.addBatch(sql);
                if(i%200==0){
                    //執(zhí)行語句列表中的語句
                    st.executeBatch();
                    //清空語句列表中的sal
                    st.clearBatch();
                }
            }
            //執(zhí)行語句列剩下的sql
            st.executeBatch();
        } catch (SQLException e) {
            e.printStackTrace();
        }finally {
            JdbcUtil.close(null, st, conn);
        }
    }
    
    public static void deleteByEmpNos(int[] empNos){
        Connection conn=null;
        PreparedStatement ps=null;
        try {
            conn=JdbcUtil.getConnection();
            String sql="delete from emp where empno=?";
            ps=conn.prepareStatement(sql);
            for(int empNo: empNos){
                ps.setInt(1, empNo);
                ps.addBatch();
            }
            ps.executeBatch();
            ps.clearBatch();
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            JdbcUtil.close(null, ps, conn);
        }
    }

}