python模塊-pymysql源碼分析及其常見使用

D:\soft\python36\Lib\site-packages\pymysql>tree /f
卷 新加捲 的文件夾 PATH 列表
卷序列號爲 960E-961E
D:.
│  charset.py
│  connections.py
│  converters.py
│  cursors.py
│  err.py
│  optionfile.py
│  protocol.py
│  times.py
│  util.py
│  _auth.py
│  _compat.py
│  _socketio.py
│  __init__.py
│
├─constants
│  │  CLIENT.py
│  │  COMMAND.py
│  │  CR.py
│  │  ER.py
│  │  FIELD_TYPE.py
│  │  FLAG.py
│  │  SERVER_STATUS.py
│  │  __init__.py
│  │
│  └─__pycache__
│          CLIENT.cpython-36.pyc
│          COMMAND.cpython-36.pyc
│          CR.cpython-36.pyc
│          ER.cpython-36.pyc
│          FIELD_TYPE.cpython-36.pyc
│          FLAG.cpython-36.pyc
│          SERVER_STATUS.cpython-36.pyc
│          __init__.cpython-36.pyc
│
└─__pycache__
        charset.cpython-36.pyc
        connections.cpython-36.pyc
        converters.cpython-36.pyc
        cursors.cpython-36.pyc
        err.cpython-36.pyc
        optionfile.cpython-36.pyc
        protocol.cpython-36.pyc
        times.cpython-36.pyc
        util.cpython-36.pyc
        _auth.cpython-36.pyc
        _compat.cpython-36.pyc
        _socketio.cpython-36.pyc
        __init__.cpython-36.pyc

pymysql源碼目錄結構

 

# -*- coding: utf-8 -*-
# @Time : 2019/8/14 10:38
# @Author : wangmengmeng
import pymysql
from config.cfg import *


class ConnectDB:
    def __init__(self):
        print('start connecting MySQL...')
        try:
            self.host = host
            self.port = int(port)
            self.username = user_name
            self.password = pwd
            self.db_sf_full = db_auditcenter
        except Exception as e:
            print(e)
        else:
            print("數據庫鏈接成功！")

    def connect(self):
        return pymysql.Connect(host=self.host, port=self.port, user=self.username, passwd=self.password,
                               database=self.db_sf_full, charset='utf8')



if __name__ == '__main__':
    con = ConnectDB()
    # cur = con.connect().cursor() # 返回格式爲 元組裏嵌套元組
    """
    如：((1002, '3', 'wangmm', '王萌萌', '122', '122', 0, datetime.datetime(2020, 3, 9, 14, 28, 18), None), (12002, '3', 'wangmm', '王萌萌', 'vvv', 'vvv', 0, datetime.datetime(2020, 3, 13, 13, 43, 11), None))
    """
    cur = con.connect().cursor(pymysql.cursors.DictCursor) # 返回格式爲 列表裏嵌套字典
    """
    如：[{'id': 1002, 'pharmacist_id': '3', 'pharmacist_name': 'wangmm', 'pharmacist_realname': '王萌萌', 'tag': '122', 'tag_py': '122', 'default_flag': 0, 'created_time': datetime.datetime(2020, 3, 9, 14, 28, 18), 'modified_time': None}, {'id': 12002, 'pharmacist_id': '3', 'pharmacist_name': 'wangmm', 'pharmacist_realname': '王萌萌', 'tag': 'vvv', 'tag_py': 'vvv', 'default_flag': 0, 'created_time': datetime.datetime(2020, 3, 13, 13, 43, 11), 'modified_time': None}]
    """
    cur.execute('SELECT * FROM `sf_collect_tag`')
    # print(cur.fetchone())  # 查詢一條數據，返回一維元組，若查詢結果集有多條，則只會取最上面一條，若沒有結果則返回None
    # print(cur.fetchall())  # 查詢多條數據，返回二維元組，若沒有結果則返回()
    print(cur.fetchmany(2))  # 查詢指定條數據