# __Desc__ = 从数据库中导出数据到excel数据表中
import xlwt
import pymysql
class MYSQL:
  def __init__(self):
    pass
  def __del__(self):
    self._cursor.close()
    self._connect.close()
  def connectDB(self):
    """
    连接数据库
    :return:
    """
    try:
      self._connect = pymysql.Connect(
        host='localhost',
        port=3306,
        user='root',
        passwd='123456',
        db='test',
        charset='utf8'
      )
      return 0
    except:
      return -1
  def export(self, table_name, output_path):
    self._cursor = self._connect.cursor()
    count = self._cursor.execute('select * from '+table_name)
    # print(self._cursor.lastrowid)
    print(count)
    # 重置游标的位置
    self._cursor.scroll(0, mode='absolute')
    # 搜取所有结果
    results = self._cursor.fetchall()
    # 获取MYSQL里面的数据字段名称
    fields = self._cursor.description
    workbook = xlwt.Workbook()
    # 注意: 在add_sheet时, 置参数cell_overwrite_ok=True, 可以覆盖原单元格中数据。
    # cell_overwrite_ok默认为False, 覆盖的话, 会抛出异常.
    sheet = workbook.add_sheet('table_'+table_name, cell_overwrite_ok=True)
    # 写上字段信息
    for field in range(0, len(fields)):
      sheet.write(0, field, fields[field][0])
    # 获取并写入数据段信息
    row = 1
    col = 0
    for row in range(1,len(results)+1):
      for col in range(0, len(fields)):
        sheet.write(row, col, u'%s' % results[row-1][col])
    workbook.save(output_path)
if __name__ == '__main__':
  mysql = MYSQL()
  flag = mysql.connectDB()
  if flag == -1:
    print('数据库连接失败')
  else:
    print('数据库连接成功')
    mysql.export('employee', 'E:/test_input.xls')