华山资源网

python 连接各类主流数据库的实例代码
脚本专栏 2024/11/18 佚名
3 1

本篇博文主要介绍Python连接各种数据库的方法及简单使用

包括关系数据库：sqlite,mysql,mssql

非关系数据库：MongoDB,Redis

代码写的比较清楚，直接上代码

1.连接sqlite

# coding=utf-8
# http://www.runoob.com/sqlite/sqlite-python.html
import sqlite3
import traceback

try:
 # 如果表不存在,就创建
 with sqlite3.connect('test.db') as conn:

  print("Opened database successfully")

  # 删除表
  conn.execute("DROP TABLE IF EXISTS COMPANY")

  # 创建表
  sql = """
     CREATE TABLE IF NOT EXISTS COMPANY
    (ID INTEGER PRIMARY KEY  AUTOINCREMENT,
    NAME   TEXT NOT NULL,
    AGE   INT  NOT NULL,
    ADDRESS  CHAR(50),
    SALARY   REAL);
  """
  conn.execute(sql)

  print("create table successfully")

  # 添加数据
  conn.executemany("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES (",
       [('Paul', 32, 'California', 20000.00),
       ('Allen', 25, 'Texas', 15000.00),
       ('Teddy', 23, 'Norway', 20000.00),
       ('Mark', 25, 'Rich-Mond ', 65000.00),
       ('David', 27, 'Texas', 85000.00),
       ('Kim', 22, 'South-Hall', 45000.00),
       ('James', 24, 'Houston', 10000.00)])
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ( 'Paul', 32, 'California', 20000.00 )")
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ('Allen', 25, 'Texas', 15000.00 )")
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ('Teddy', 23, 'Norway', 20000.00 )")
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ( 'Mark', 25, 'Rich-Mond ', 65000.00 )")
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ( 'David', 27, 'Texas', 85000.00 )");
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ( 'Kim', 22, 'South-Hall', 45000.00 )")
  #
  # conn.execute("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY)  # VALUES ( 'James', 24, 'Houston', 10000.00 )")

  # 提交,否则重新运行程序时,表中无数据
  conn.commit()
  print("insert successfully")

  # 查询表
  sql = """
   select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
   """

  result = conn.execute(sql)

  for row in result:
   print("-" * 50) # 输出50个-,作为分界线
   print("%-10s %s" % ("id", row[0])) # 字段名固定10位宽度,并且左对齐
   print("%-10s %s" % ("name", row[1]))
   print("%-10s %s" % ("age", row[2]))
   print("%-10s %s" % ("address", row[3]))
   print("%-10s %.2f" % ("salary", row[4]))
   # or
   # print('{:10s} {:.2f}'.format("salary", row[4]))


except sqlite3.Error as e:
 print("sqlite3 Error:", e)
 traceback.print_exc()

2.连接mysql

2.1使用mysqldb库中的_mysql

#! /usr/bin/env python2.7
# coding=utf-8
# Created by xiaosanyu at 16/5/30

# mysqldb 只支持python2.7
# http://mysql-python.sourceforge.net/

import MySQLdb
from contextlib import closing
import traceback

try:
 # 获取一个数据库连接
 with closing(MySQLdb.connect(host='localhost', user='root', passwd='root', db='test', port=3306,charset='utf8')) as conn:
  print("connect database successfully")
  with closing(conn.cursor()) as cur:
   # 删除表
   cur.execute("DROP TABLE IF EXISTS COMPANY")
   # 创建表
   sql = """
      CREATE TABLE IF NOT EXISTS COMPANY
     (ID INTEGER PRIMARY KEY NOT NULL auto_increment,
     NAME   TEXT NOT NULL,
     AGE   INT  NOT NULL,
     ADDRESS  CHAR(50),
     SALARY   REAL);
   """
   cur.execute(sql)

   print("create table successfully")

   # 添加数据
   # 在一个conn.execute里面里面执行多个sql语句是非法的
   cur.executemany("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES ( %s, %s, %s, %s )",
       [('Paul', 32, 'California', 20000.00),
        ('Allen', 25, 'Texas', 15000.00),
        ('Teddy', 23, 'Norway', 20000.00),
        ('Mark', 25, 'Rich-Mond ', 65000.00),
        ('David', 27, 'Texas', 85000.00),
        ('Kim', 22, 'South-Hall', 45000.00),
        ('James', 24, 'Houston', 10000.00)])

   # 提交,否则重新运行程序时,表中无数据
   conn.commit()
   print("insert successfully")

   # 查询表
   sql = """
    select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
    """

   cur.execute(sql)

   for row in cur.fetchall():
    print("-" * 50) # 输出50个-,作为分界线
    print("%-10s %s" % ("id", row[0])) # 字段名固定10位宽度,并且左对齐
    print("%-10s %s" % ("name", row[1]))
    print("%-10s %s" % ("age", row[2]))
    print("%-10s %s" % ("address", row[3]))
    print("%-10s %s" % ("salary", row[4]))

except MySQLdb.Error as e:
 print("Mysql Error:", e)
 traceback.print_exc() # 打印错误栈信息

2.2 使用MySQLdb

#! /usr/bin/env python2.7
# coding=utf-8
# Created by xiaosanyu at 16/5/30

# mysqldb 只支持python2.7
# http://mysql-python.sourceforge.net/

import MySQLdb
from contextlib import closing
import traceback

try:
 # 获取一个数据库连接
 with closing(MySQLdb.connect(host='localhost', user='root', passwd='root', db='test', port=3306,charset='utf8')) as conn:
  print("connect database successfully")
  with closing(conn.cursor()) as cur:
   # 删除表
   cur.execute("DROP TABLE IF EXISTS COMPANY")
   # 创建表
   sql = """
      CREATE TABLE IF NOT EXISTS COMPANY
     (ID INTEGER PRIMARY KEY NOT NULL auto_increment,
     NAME   TEXT NOT NULL,
     AGE   INT  NOT NULL,
     ADDRESS  CHAR(50),
     SALARY   REAL);
   """
   cur.execute(sql)

   print("create table successfully")

   # 添加数据
   # 在一个conn.execute里面里面执行多个sql语句是非法的
   cur.executemany("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES ( %s, %s, %s, %s )",
       [('Paul', 32, 'California', 20000.00),
        ('Allen', 25, 'Texas', 15000.00),
        ('Teddy', 23, 'Norway', 20000.00),
        ('Mark', 25, 'Rich-Mond ', 65000.00),
        ('David', 27, 'Texas', 85000.00),
        ('Kim', 22, 'South-Hall', 45000.00),
        ('James', 24, 'Houston', 10000.00)])

   # 提交,否则重新运行程序时,表中无数据
   conn.commit()
   print("insert successfully")

   # 查询表
   sql = """
    select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
    """

   cur.execute(sql)

   for row in cur.fetchall():
    print("-" * 50) # 输出50个-,作为分界线
    print("%-10s %s" % ("id", row[0])) # 字段名固定10位宽度,并且左对齐
    print("%-10s %s" % ("name", row[1]))
    print("%-10s %s" % ("age", row[2]))
    print("%-10s %s" % ("address", row[3]))
    print("%-10s %s" % ("salary", row[4]))

except MySQLdb.Error as e:
 print("Mysql Error:", e)
 traceback.print_exc() # 打印错误栈信息

2.3使用pymysql

2.1和2.2节使用MySQLdb，不支持Python3.x

pymysql对Python2.x和Python3.x的支持都比较好

# Created by xiaosanyu at 16/5/30
# coding=utf-8

# https://github.com/PyMySQL/PyMySQL/
import pymysql
from contextlib import closing
import traceback

try:
 # 获取一个数据库连接,with关键字 表示退出时,conn自动关闭
 # with 嵌套上一层的with 要使用closing()
 with closing(pymysql.connect(host='localhost', user='root', passwd='root', db='test', port=3306,
         charset='utf8')) as conn:

  print("connect database successfully")

  # 获取游标,with关键字 表示退出时,cur自动关闭
  with conn.cursor() as cur:
   # 删除表
   cur.execute("DROP TABLE IF EXISTS COMPANY")
   # 创建表
   sql = """
      CREATE TABLE IF NOT EXISTS COMPANY
     (ID INTEGER PRIMARY KEY NOT NULL auto_increment,
     NAME   TEXT NOT NULL,
     AGE   INT  NOT NULL,
     ADDRESS  CHAR(50),
     SALARY   REAL);
   """
   cur.execute(sql)

   print("create table successfully")

   # 添加数据
   # 在一个conn.execute里面里面执行多个sql语句是非法的
   cur.executemany("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES ( %s, %s, %s, %s )",
       [('Paul', 32, 'California', 20000.00),
        ('Allen', 25, 'Texas', 15000.00),
        ('Teddy', 23, 'Norway', 20000.00),
        ('Mark', 25, 'Rich-Mond ', 65000.00),
        ('David', 27, 'Texas', 85000.00),
        ('Kim', 22, 'South-Hall', 45000.00),
        ('James', 24, 'Houston', 10000.00)])

   # 提交,否则重新运行程序时,表中无数据
   conn.commit()
   print("insert successfully")

   # 查询表
   sql = """
    select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
    """

   cur.execute(sql)

   for row in cur.fetchall():
    print("-" * 50) # 输出50个-,作为分界线
    print("%-10s %s" % ("id", row[0])) # 字段名固定10位宽度,并且左对齐
    print("%-10s %s" % ("name", row[1]))
    print("%-10s %s" % ("age", row[2]))
    print("%-10s %s" % ("address", row[3]))
    print("%-10s %s" % ("salary", row[4]))
except pymysql.Error as e:
 print("Mysql Error:", e)
 traceback.print_exc()

3.连接mssql

# Created by xiaosanyu at 16/5/30

# http://www.pymssql.org/en/latest/
import pymssql
from contextlib import closing

try:
 # 先要保证数据库中有test数据库
 # 获取一个数据库连接,with关键字 表示退出时,conn自动关闭
 # with 嵌套上一层的with 要使用closing()
 with closing(pymssql.connect(host='192.168.100.114', user='sa', password='sa12345', database='test', port=1433,
         charset='utf8')) as conn:

  print("connect database successfully")

  # 获取游标,with关键字 表示退出时,cur自动关闭
  with conn.cursor() as cur:
   # 删除表
   cur.execute(
     '''if exists (select 1 from sys.objects where name='COMPANY' and type='U') drop table COMPANY''')
   # 创建表
   sql = """
      CREATE TABLE COMPANY
     (ID INT IDENTITY(1,1) PRIMARY KEY NOT NULL ,
     NAME   TEXT NOT NULL,
     AGE   INT  NOT NULL,
     ADDRESS  CHAR(50),
     SALARY   REAL);
   """
   cur.execute(sql)

   print("create table successfully")

   # 添加数据
   # 在一个conn.execute里面里面执行多个sql语句是非法的
   cur.executemany("INSERT INTO COMPANY (NAME,AGE,ADDRESS,SALARY) VALUES ( %s, %s, %s, %s )",
       [('Paul', 32, 'California', 20000.00),
        ('Allen', 25, 'Texas', 15000.00),
        ('Teddy', 23, 'Norway', 20000.00),
        ('Mark', 25, 'Rich-Mond', 65000.00),
        ('David', 27, 'Texas', 85000.00),
        ('Kim', 22, 'South-Hall', 45000.00),
        ('James', 24, 'Houston', 10000.00)])

   # 提交,否则重新运行程序时,表中无数据
   conn.commit()
   print("insert successfully")

   # 查询表
   sql = """
    select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
    """

   cur.execute(sql)

   for row in cur.fetchall():
    print("-" * 50) # 输出50个-,作为分界线
    print("%-10s %s" % ("id", row[0])) # 字段名固定10位宽度,并且左对齐
    print("%-10s %s" % ("name", row[1]))
    print("%-10s %s" % ("age", row[2]))
    print("%-10s %s" % ("address", row[3]))
    print("%-10s %s" % ("salary", row[4]))
except pymssql.Error as e:
 print("mssql Error:", e)
 # traceback.print_exc()

4.连接MongoDB

# Created by xiaosanyu at 16/5/30

# https://docs.mongodb.com/ecosystem/drivers/python/
# https://pypi.python.org/pypi/pymongo/

import pymongo
from pymongo.mongo_client import MongoClient
import pymongo.errors
import traceback

try:
 # 连接到 mongodb 服务
 mongoClient = MongoClient('localhost', 27017)
 # 连接到数据库
 mongoDatabase = mongoClient.test
 print("connect database successfully")

 # 获取集合
 mongoCollection = mongoDatabase.COMPANY

 # 移除所有数据
 mongoCollection.remove()

 # 添加数据
 mongoCollection.insert_many([{"Name": "Paul", "Age": "32", "Address": "California", "Salary": "20000.00"},
         {"Name": "Allen", "Age": "25", "Address": "Texas", "Salary": "15000.00"},
         {"Name": "Teddy", "Age": "23", "Address": "Norway", "Salary": "20000.00"},
         {"Name": "Mark", "Age": "25", "Address": "Rich-Mond", "Salary": "65000.00"},
         {"Name": "David", "Age": "27", "Address": "Texas", "Salary": "85000.00"},
         {"Name": "Kim", "Age": "22", "Address": "South-Hall", "Salary": "45000.00"},
         {"Name": "James", "Age": "24", "Address": "Houston", "Salary": "10000.00"}, ])

 #获取集合中的值
 for row in mongoCollection.find():
  print("-" * 50) # 输出50个-,作为分界线
  print("%-10s %s" % ("_id", row['_id'])) # 字段名固定10位宽度,并且左对齐
  print("%-10s %s" % ("name", row['Name']))
  print("%-10s %s" % ("age", row['Age']))
  print("%-10s %s" % ("address", row['Address']))
  print("%-10s %s" % ("salary", row['Salary']))

 print('\n\n\n')
 # 使id自增
 mongoCollection.remove()
 # 创建计数表
 mongoDatabase.counters.save({"_id": "people_id", "sequence_value": 0})
 # 创建存储过程
 mongoDatabase.system_js.getSequenceValue = '''function getSequenceValue(sequenceName){
   var sequenceDocument = db.counters.findAndModify({
    query: {_id: sequenceName},
    update: {$inc:{sequence_value: 1}},
    new:true
   });
   return sequenceDocument.sequence_value;
  }'''
 mongoCollection.insert_many(
   [{"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "Paul", "Age": "32",
    "Address": "California", "Salary": "20000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "Allen", "Age": "25",
    "Address": "Texas", "Salary": "15000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "Teddy", "Age": "23",
    "Address": "Norway", "Salary": "20000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "Mark", "Age": "25",
    "Address": "Rich-Mond", "Salary": "65000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "David", "Age": "27",
    "Address": "Texas", "Salary": "85000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "Kim", "Age": "22",
    "Address": "South-Hall", "Salary": "45000.00"},
    {"_id": mongoDatabase.eval("getSequenceValue('people_id')"), "Name": "James", "Age": "24",
    "Address": "Houston", "Salary": "10000.00"}, ])

 for row in mongoCollection.find():
  print("-" * 50) # 输出50个-,作为分界线
  print("%-10s %s" % ("_id", int(row['_id']))) # 字段名固定10位宽度,并且左对齐
  print("%-10s %s" % ("name", row['Name']))
  print("%-10s %s" % ("age", row['Age']))
  print("%-10s %s" % ("address", row['Address']))
  print("%-10s %s" % ("salary", row['Salary']))
except pymongo.errors.PyMongoError as e:
 print("mongo Error:", e)
 traceback.print_exc()

5.连接Redis

5.1使用redis

# coding=utf-8
# Created by xiaosanyu at 16/5/31

# https://pypi.python.org/pypi/redis/2.10.5
# http://redis-py.readthedocs.io/en/latest/#
import redis

r = redis.Redis(host='localhost', port=6379, db=0, password="12345")
print("connect", r.ping())

# 看信息
info = r.info()
# or 查看部分信息
# info = r.info("Server")

# 输出信息
items = info.items()
for i, (key, value) in enumerate(items):
 print("item %s----%s:%s" % (i, key, value))

# 删除键和对应的值
r.delete("company")

# 可以一次性push一条或多条数据
r.rpush("company", {"id": 1, "Name": "Paul", "Age": "32", "Address": "California", "Salary": "20000.00"},
  {"id": 2, "Name": "Allen", "Age": "25", "Address": "Texas", "Salary": "15000.00"},
  {"id": 3, "Name": "Teddy", "Age": "23", "Address": "Norway", "Salary": "20000.00"})
r.rpush("company", {"id": 4, "Name": "Mark", "Age": "25", "Address": "Rich-Mond", "Salary": "65000.00"})
r.rpush("company", {"id": 5, "Name": "David", "Age": "27", "Address": "Texas", "Salary": "85000.00"})
r.rpush("company", {"id": 6, "Name": "Kim", "Age": "22", "Address": "South-Hall", "Salary": "45000.00"})
r.rpush("company", {"id": 7, "Name": "James", "Age": "24", "Address": "Houston", "Salary": "10000.00"})

# eval用来将dict格式的字符串转换成dict
for row in map(lambda x: eval(x), r.lrange("company", 0, r.llen("company"))):
 print("-" * 50) # 输出50个-,作为分界线
 print("%-10s %s" % ("_id", row['id'])) # 字段名固定10位宽度,并且左对齐
 print("%-10s %s" % ("name", row['Name']))
 print("%-10s %s" % ("age", row['Age']))
 print("%-10s %s" % ("address", row['Address']))
 print("%-10s %s" % ("salary", row['Salary']))

# 关闭当前连接
# r.shutdown() #这个是关闭redis服务端

5.2使用pyredis

# Created by xiaosanyu at 16/5/30

# http://pyredis.readthedocs.io/en/latest/
import pyredis

r = pyredis.Client(host='localhost', port=6379, database=0, password="12345")
print("connect", r.ping().decode("utf-8"))

# 看信息

# info = r.execute("info").decode()
# or 查看部分信息
info = r.execute("info", "Server").decode()

# 输出信息
print(info)

# 删除键和对应的值
r.delete("company")

# 可以一次性push一条或多条数据
r.rpush("company", '''{"id": 1, "Name": "Paul", "Age": "32", "Address": "California", "Salary": "20000.00"}''',
  '''{"id": 2, "Name": "Allen", "Age": "25", "Address": "Texas", "Salary": "15000.00"}''',
  '''{"id": 3, "Name": "Teddy", "Age": "23", "Address": "Norway", "Salary": "20000.00"}''')
r.rpush("company", '''{"id": 4, "Name": "Mark", "Age": "25", "Address": "Rich-Mond", "Salary": "65000.00"}''')
r.rpush("company", '''{"id": 5, "Name": "David", "Age": "27", "Address": "Texas", "Salary": "85000.00"}''')
r.rpush("company", '''{"id": 6, "Name": "Kim", "Age": "22", "Address": "South-Hall", "Salary": "45000.00"}''')
r.rpush("company", '''{"id": 7, "Name": "James", "Age": "24", "Address": "Houston", "Salary": "10000.00"}''')

# eval用来将dict格式的字符串转换成dict
for row in map(lambda x: eval(x), r.lrange("company", 0, r.llen("company"))):
 print("-" * 50) # 输出50个-,作为分界线
 print("%-10s %s" % ("_id", row['id'])) # 字段名固定10位宽度,并且左对齐
 print("%-10s %s" % ("name", row['Name']))
 print("%-10s %s" % ("age", row['Age']))
 print("%-10s %s" % ("address", row['Address']))
 print("%-10s %s" % ("salary", row['Salary']))

# 关闭当前连接
r.close()

代码下载：python_connect_database

以上这篇python 连接各类主流数据库的实例代码就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。

华山资源网 Design By www.eoogi.com
广告合作：本站广告合作请联系QQ：858582 申请时备注：广告合作（否则不回）
免责声明：本站资源来自互联网收集,仅供用于学习和交流,请遵循相关法律法规,本站一切资源不代表本站立场,如有侵权、后门、不妥请联系本站删除！
华山资源网 Design By www.eoogi.com
www.eoogi.com 华山资源网
120,135影音资源
344,641技术资源
22,817软件资源
435,032站长资源

更新日志

友情链接

杰晶网络 DDR爱好者之家 桃源资源网 杰网资源 富贵资源网 南强小屋 铁雪资源网 幽灵资源网 万梅资源网 狼山资源网 白云岛资源网 昆仑资源网 相思资源网 明霞山资源网 内蒙古资源网 黑松山资源网 茶园资源网 饿虎岗资源网 大旗谷资源网 常春岛资源网 岱庙资源网 兴国资源网 快活林资源网 蝙蝠岛资源网 帝王谷资源网 白云城资源网 伏龙阁资源网 清风细雨楼 天枫庄资源网 圆月山庄资源网 无争山庄资源网 神水资源网 移花宫资源网 神剑山庄资源网 无为清净楼资源网 金钱帮资源网 丐帮资源网 华山资源网 极乐门资源网 小李飞刀资源网 凤求凰客栈 风云阁资源网 金狮镖局 鸳鸯亭资源网 千金楼资源网 更多链接
华山资源网 Design By www.eoogi.com