Python connection to MySQL MongoDB Redis memcache and other database methods
- 2020-04-02 13:13:34
- OfStack
I have been writing scripts with Python for a long time, and I often operate on database (MySQL). Now I will sort out the operation of various kinds of database. If there are new parameters in the back, I will make up for them.
one
Python MySQL operation
: for details:
【 apt-get install python-mysqldb 】
#!/bin/env python
# -*- encoding: utf-8 -*-
#-------------------------------------------------------------------------------
# Purpose: example for python_to_mysql
# Author: zhoujy
# Created: 2013-06-14
# update: 2013-06-14
#-------------------------------------------------------------------------------
import MySQLdb
import os
# Establish a connection to the database system, format
#conn = MySQLdb.connect(host='localhost',user='root',passwd='123456',db='test',port=3306,charset='utf8')
# Specify the configuration file and determine the directory , Or we could write the absolute path
cwd = os.path.realpath(os.path.dirname(__file__))
db_conf = os.path.join(cwd, 'db.conf')
conn = MySQLdb.connect(read_default_file=db_conf,host='localhost',db='test',port=3306,charset='utf8')
# To perform the sql statements
query = 'select id from t1'
# Get operation cursor
cursor = conn.cursor()
# perform SQL
cursor.execute(query)
# Get a record , Each record is returned as a tuple , return 3 , the cursor points to 2 Records.
result1 = cursor.fetchone()
for i in result1:
print i
# Returns the number of rows affected
print cursor.rowcount
# Gets the specified number of records , Each record is returned as a tuple , return 1 . 2 , cursor from the first 2 The cursor points to no 4 Records.
result2 = cursor.fetchmany(2)
for i in result2:
for ii in i:
print ii
# Get all the records , Each record is returned as a tuple , return 3 . 4 . 7 . 6, The cursor from the first 4 A record starts at the end.
result3 = cursor.fetchall()
for i in result3:
for ii in i:
print ii
# Get all the records , Each record is returned as a tuple , return 3 . 4 . 7 . 6, The cursor from the first 1 Strip start
# Reset cursor position, 0 Is the offset, mode = absolute | relative, The default is relative
cursor.scroll(0,mode='absolute')
result3 = cursor.fetchall()
for i in result3:
for ii in i:
print ii
# The following 2 Each method can insert data into the database:
#(one)
for i in range (10,20):
query2 = 'insert into t1 values("%d",now())' %i
cursor.execute(query2)
# submit
conn.rollback()
#(two)
rows = []
for i in range (10,20):
rows.append(i)
query2 = 'insert into t1 values("%s",now())'
#executemany 2 A parameter , The first 2 All parameters are variables.
cursor.executemany(query2,rows)
# submit
conn.commit()
# Select database
query3 = 'select id from dba_hospital'
# Reselect database
conn.select_db('chushihua')
cursor.execute(query3)
result4 = cursor.fetchall()
for i in result4:
for ii in i:
print ii
# Does not define query , direct execution:
cursor.execute("set session binlog_format='mixed'")
# Close the cursor to free the resource
cursor.close()
'''
+------+---------------------+
| id | modifyT |
+------+---------------------+
| 3 | 2010-01-01 00:00:00 |
| 1 | 2010-01-01 00:00:00 |
| 2 | 2010-01-01 00:00:00 |
| 3 | 2010-01-01 00:00:00 |
| 4 | 2013-06-04 17:04:54 |
| 7 | 2013-06-04 17:05:36 |
| 6 | 2013-06-04 17:05:17 |
+------+---------------------+
'''
Note: in scripts, passwords written in scripts are easily exposed, so you can store them in a configuration file, such as db.conf:
[client]
user=root
password=123456
two Python operation mongo :
#!/bin/env python
# -*- encoding: utf-8 -*-
#-------------------------------------------------------------------------------
# Purpose: example for python_to_mongodb
# Author: zhoujy
# Created: 2013-06-14
# update: 2013-06-14
#-------------------------------------------------------------------------------
import pymongo
import os
# Establish a connection to the database system , create Connection When the specified host and port parameter
conn = pymongo.Connection(host='127.0.0.1',port=27017)
#admin Database has account, connection - certification - Switch the library
db_auth = conn.admin
db_auth.authenticate('sa','sa')
# Connect to database
db = conn.abc
# Join table
collection = db.stu
# View all table names
db.collection_names()
#print db.collection_names()
# Access the data of the table, specifying the columns
item = collection.find({},{"sname":1,"course":1,"_id":0})
for rows in item:
print rows.values()
# Accessing a row of data in a table
print collection.find_one()
# I get all the columns
for rows in collection.find_one():
print rows
# insert
collection.insert({"sno":100,"sname":"jl","course":{"D":80,"S":85}})
# or
u = dict(sno=102,sname='zjjj',course={"D":80,"S":85})
collection.insert(u)
# Get the number of rows
print collection.find().count()
print collection.find({"sno":100})
# Sort by the value of a column. pymongo.DESCENDING: Reverse order. pymongo.ASCENDING: Ascending order. In accordance with the sno Reverse order
item = collection.find().sort('sno',pymongo.DESCENDING)
for rows in item:
print rows.values()
# Multi-column sorting
item = collection.find().sort([('sno',pymongo.DESCENDING),('A',pymongo.ASCENDING)])
# Update, the first parameter is the condition, the second parameter is the update operation, $set,%inc,$push,$ne,$addToSet,$rename Etc.
collection.update({"sno":100},{"$set":{"sno":101}})
# Updates multiple rows and columns
collection.update({"sno":102},{"$set":{"sno":105,"sname":"SSSS"}},multi=True)
# Delete, the first parameter is the condition, the second parameter is the delete operation.
collection.remove({"sno":101})
'''
sno: Student id. sname : name; course Subject:
db.stu.insert({"sno":1,"sname":" Zhang SAN ","course":{"A":95,"B":90,"C":65,"D":74,"E":100}})
db.stu.insert({"sno":2,"sname":" Li si ","course":{"A":90,"B":85,"X":75,"Y":64,"Z":95}})
db.stu.insert({"sno":3,"sname":" Zhao Wu ","course":{"A":70,"B":56,"F":85,"G":84,"H":80}})
db.stu.insert({"sno":4,"sname":"zhoujy","course":{"A":64,"B":60,"C":95,"T":94,"Y":85}})
db.stu.insert({"sno":5,"sname":"abc","course":{"A":87,"B":70,"Z":56,"G":54,"H":75}})
db.stu.insert({"sno":6,"sname":" Six Yang ","course":{"A":65,"U":80,"C":78,"R":75,"N":90}})
db.stu.insert({"sno":7,"sname":" Chen 2 ","course":{"A":95,"M":68,"N":84,"S":79,"K":89}})
db.stu.insert({"sno":8,"sname":"zhoujj","course":{"P":90,"B":77,"J":85,"K":68,"L":80}})
db.stu.insert({"sno":9,"sname":"ccc","course":{"Q":85,"B":86,"C":90,"V":87,"U":85}})
'''
Calculate the number of collections in the Mongodb document:
import pymongo
conn = pymongo.Connection(host='127.0.0.1',port=27017)
db = conn.abc #abc The document
for tb_name in db.collection_names(): # Loop out the collection names
Count = db[tb_name].count() # Calculate the number of sets
if Count > 2: # Filter conditions
print tb_name + ':' + str(Count)
'''
conn = pymongo.Connection(host='127.0.0.1',port=27017)
db = conn.abc
for tb_name in db.collection_names():
print tb_name + ':'
exec('print ' + 'db.'+tb_name+'.count()') # Variables are handled as collections
OR
conn = pymongo.Connection(host='127.0.0.1',port=27017)
db = conn.abc
for tb_name in db.collection_names():
mon_dic=db.command("collStats", tb_name) # Returns in dictionary form
print mon_dic.get('ns'),mon_dic.get('count')
'''
Three, Python operation Redis :
#!/bin/env python
# -*- encoding: utf-8 -*-
#-------------------------------------------------------------------------------
# Purpose: example for python_to_mongodb
# Author: zhoujy
# Created: 2013-06-14
# update: 2013-06-14
#-------------------------------------------------------------------------------
import redis
f = open('aa.txt')
while True:
line = f.readline().strip().split(' # ')
if line == ['']:
break
UserName,Pwd,Email = line
# print name.strip(),pwd.strip(),email.strip()
rc = redis.StrictRedis(host='127.0.0.1',port=6379,db=15)
rc.hset('Name:' + UserName,'Email',Email)
rc.hset('Name:' + UserName,'Password',Pwd)
f.close()
alluser = rc.keys('*')
#print alluser
print "=================================== Read the stored data ==================================="
for user in alluser:
print ' # '.join((user.split(':')[1],rc.hget(user,'Password'),rc.hget(user,'Email')))
Four, Python operation memcache :
import memcache
mc = memcache.Client(['127.0.0.1:11211'],debug=1)
#!/usr/bin/env python
#coding=utf-8
import MySQLdb
import memcache
import sys
import time
def get_data(mysql_conn):
# nn = raw_input("press string name:")
mc = memcache.Client(['127.0.0.1:11211'],debug=1)
t1 =time.time()
value = mc.get('zhoujinyia')
if value == None:
t1 = time.time()
print t1
query = "select company,email,sex,address from uc_user_offline where realName = 'zhoujinyia'"
cursor= mysql_conn.cursor()
cursor.execute(query)
item = cursor.fetchone()
t2 = time.time()
print t2
t = round(t2-t1)
print "from mysql cost %s sec" %t
print item
mc.set('zhoujinyia',item,60)
else :
t2 = time.time()
t=round(t2-t1)
print "from memcache cost %s sec" %t
print value
if __name__ =='__main__':
mysql_conn = MySQLdb.connect(host='127.0.0.1',user='root',passwd='123456',db='member',port=3306,charset='utf8')
get_data(mysql_conn)