import threading
class MyThread(threading.Thread):
  def __init__(self, name, count, exec_object):
    threading.Thread.__init__(self)
    self.name = name
    self.count = count
    self.exec_object = exec_object
  def run(self):
    while self.count >= 0:
      count = count - 1
      self.exec_object.execFunc(count)
thread1 = MyThread('MyThread1', 3, ExecObject())
thread2 = MyThread('MyThread2', 5, ExecObject())
thread1.start()
thread2.start()
thread1.join() # join方法 执行完thread1的方法才继续主线程
thread2.join() # join方法 执行完thread2的方法才继续主线程
# 执行顺序 并发执行thread1 thread2，thread1和thread2执行完成才继续执行主线程
# ExecObject类是自定义数据库操作的业务逻辑类
#
########join方法详解########
thread1 = MyThread('MyThread1', 3, ExecObject())
thread2 = MyThread('MyThread2', 5, ExecObject())
thread1.start()
thread1.join() # join方法 执行完thread1的方法才继续主线程
thread2.start()
thread2.join() # join方法 执行完thread2的方法才继续主线程
# 执行顺序 先执行thread1，执行完thread1再执行thread2，执行完thread2才继续执行主线程

import MySQLdb
from DBUtils.PooledDB import PooledDB
class MySQL:
  host = 'localhost'
  user = 'root'
  port = 3306
  pasword = ''
  db = 'testDB'
  charset = 'utf8'
  pool = None
  limit_count = 3 # 最低预启动数据库连接数量
  def __init__(self):
    self.pool = PooledDB(MySQLdb, self.limit_count, host = self.host, user = self.user, passwd = self.pasword, db = self.db,
      port = self.port, charset = self.charset, use_unicode = True)
  def select(self, sql):
    conn = self.pool.connection()
    cursor = conn.cursor()
    cursor.execute(sql)
    result = cursor.fetchall()
    cursor.close()
    conn.close()
    return result
  def insert(self, table, sql):
    conn = self.pool.connection()
    cursor = conn.cursor()
    try:
      cursor.execute(sql)
      conn.commit()
      return {'result':True, 'id':int(cursor.lastrowid)}
    except Exception as err:
      conn.rollback()
      return {'result':False, 'err':err}
    finally:
      cursor.close()
      conn.close()