python 連線各類主流資料庫簡單示例
阿新 • • 發佈:2019-02-14
本篇博文主要介紹Python連線各種資料庫的方法及簡單使用
包括關係資料庫:sqlite,mysql,mssql
非關係資料庫:MongoDB,Redis
程式碼寫的比較清楚,直接上程式碼
1.連線sqlite
# coding=utf-8
# http://www.runoob.com/sqlite/sqlite-python.html
import sqlite3
import traceback
try:
# 如果表不存在,就建立
with sqlite3.connect('test.db') as conn:
print("Opened database successfully" )
# 刪除表
conn.execute("DROP TABLE IF EXISTS COMPANY")
# 建立表
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")
# 新增資料
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,否則重新執行程式時,表中無資料
conn.commit()
print("insert successfully")
# 查詢表
sql = """
select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
"""
result = conn.execute(sql)
for row in result:
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("id", row[0])) # 欄位名固定10位寬度,並且左對齊
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.連線mysql
2.1使用mysqldb庫中的_mysql
#! /usr/bin/env python2.7
# coding=utf-8
# Created by xiaosanyu at 16/5/30
# mysqldb 只支援python2.7
# http://mysql-python.sourceforge.net/
import MySQLdb
from contextlib import closing
import traceback
try:
# 獲取一個數據庫連線
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:
# 刪除表
cur.execute("DROP TABLE IF EXISTS COMPANY")
# 建立表
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")
# 新增資料
# 在一個conn.execute裡面裡面執行多個sql語句是非法的
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,否則重新執行程式時,表中無資料
conn.commit()
print("insert successfully")
# 查詢表
sql = """
select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
"""
cur.execute(sql)
for row in cur.fetchall():
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("id", row[0])) # 欄位名固定10位寬度,並且左對齊
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() # 列印錯誤棧資訊
2.2 使用MySQLdb
#! /usr/bin/env python2.7
# coding=utf-8
# Created by xiaosanyu at 16/5/30
# mysqldb 只支援python2.7
# http://mysql-python.sourceforge.net/
import MySQLdb
from contextlib import closing
import traceback
try:
# 獲取一個數據庫連線
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:
# 刪除表
cur.execute("DROP TABLE IF EXISTS COMPANY")
# 建立表
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")
# 新增資料
# 在一個conn.execute裡面裡面執行多個sql語句是非法的
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,否則重新執行程式時,表中無資料
conn.commit()
print("insert successfully")
# 查詢表
sql = """
select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
"""
cur.execute(sql)
for row in cur.fetchall():
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("id", row[0])) # 欄位名固定10位寬度,並且左對齊
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() # 列印錯誤棧資訊
2.3使用pymysql
2.1和2.2節使用MySQLdb,不支援Python3.x
pymysql對Python2.x和Python3.x的支援都比較好
# Created by xiaosanyu at 16/5/30
# coding=utf-8
# https://github.com/PyMySQL/PyMySQL/
import pymysql
from contextlib import closing
import traceback
try:
# 獲取一個數據庫連線,with關鍵字 表示退出時,conn自動關閉
# with 巢狀上一層的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")
# 獲取遊標,with關鍵字 表示退出時,cur自動關閉
with conn.cursor() as cur:
# 刪除表
cur.execute("DROP TABLE IF EXISTS COMPANY")
# 建立表
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")
# 新增資料
# 在一個conn.execute裡面裡面執行多個sql語句是非法的
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,否則重新執行程式時,表中無資料
conn.commit()
print("insert successfully")
# 查詢表
sql = """
select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
"""
cur.execute(sql)
for row in cur.fetchall():
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("id", row[0])) # 欄位名固定10位寬度,並且左對齊
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.連線mssql
# Created by xiaosanyu at 16/5/30
# http://www.pymssql.org/en/latest/
import pymssql
from contextlib import closing
try:
# 先要保證資料庫中有test資料庫
# 獲取一個數據庫連線,with關鍵字 表示退出時,conn自動關閉
# with 巢狀上一層的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")
# 獲取遊標,with關鍵字 表示退出時,cur自動關閉
with conn.cursor() as cur:
# 刪除表
cur.execute(
'''if exists (select 1 from sys.objects where name='COMPANY' and type='U') drop table COMPANY''')
# 建立表
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")
# 新增資料
# 在一個conn.execute裡面裡面執行多個sql語句是非法的
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,否則重新執行程式時,表中無資料
conn.commit()
print("insert successfully")
# 查詢表
sql = """
select id,NAME,AGE,ADDRESS,SALARY FROM COMPANY
"""
cur.execute(sql)
for row in cur.fetchall():
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("id", row[0])) # 欄位名固定10位寬度,並且左對齊
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.連線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:
# 連線到 mongodb 服務
mongoClient = MongoClient('localhost', 27017)
# 連線到資料庫
mongoDatabase = mongoClient.test
print("connect database successfully")
# 獲取集合
mongoCollection = mongoDatabase.COMPANY
# 移除所有資料
mongoCollection.remove()
# 新增資料
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"}, ])
#獲取集合中的值
for row in mongoCollection.find():
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("_id", row['_id'])) # 欄位名固定10位寬度,並且左對齊
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()
# 建立計數表
mongoDatabase.counters.save({"_id": "people_id", "sequence_value": 0})
# 建立儲存過程
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) # 輸出50個-,作為分界線
print("%-10s %s" % ("_id", int(row['_id']))) # 欄位名固定10位寬度,並且左對齊
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.連線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())
# 看資訊
info = r.info()
# or 檢視部分資訊
# info = r.info("Server")
# 輸出資訊
items = info.items()
for i, (key, value) in enumerate(items):
print("item %s----%s:%s" % (i, key, value))
# 刪除鍵和對應的值
r.delete("company")
# 可以一次性push一條或多條資料
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用來將dict格式的字串轉換成dict
for row in map(lambda x: eval(x), r.lrange("company", 0, r.llen("company"))):
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("_id", row['id'])) # 欄位名固定10位寬度,並且左對齊
print("%-10s %s" % ("name", row['Name']))
print("%-10s %s" % ("age", row['Age']))
print("%-10s %s" % ("address", row['Address']))
print("%-10s %s" % ("salary", row['Salary']))
# 關閉當前連線
# r.shutdown() #這個是關閉redis服務端
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"))
# 看資訊
# info = r.execute("info").decode()
# or 檢視部分資訊
info = r.execute("info", "Server").decode()
# 輸出資訊
print(info)
# 刪除鍵和對應的值
r.delete("company")
# 可以一次性push一條或多條資料
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用來將dict格式的字串轉換成dict
for row in map(lambda x: eval(x), r.lrange("company", 0, r.llen("company"))):
print("-" * 50) # 輸出50個-,作為分界線
print("%-10s %s" % ("_id", row['id'])) # 欄位名固定10位寬度,並且左對齊
print("%-10s %s" % ("name", row['Name']))
print("%-10s %s" % ("age", row['Age']))
print("%-10s %s" % ("address", row['Address']))
print("%-10s %s" % ("salary", row['Salary']))
# 關閉當前連線
r.close()
歡迎交流溝通~