Python脚本之django---mysql-记录主机性能数据到数据库-web站点管理数据库及web显示命令执行结果

本文涉及的产品
云数据库 RDS MySQL Serverless,0.5-2RCU 50GB
简介:

##############################################################环境

[root@LVS1 python]# cat /etc/redhat-release 

Red Hat Enterprise Linux Server release 6.4 (Santiago)

You have new mail in /var/spool/mail/root

[root@LVS1 python]# python -V

Python 2.6.6

[root@LVS1 python]#

#############################################################安装paramiko

[root@LVS1 ~]# yum install gcc

[root@LVS1 ~]# yum install python-devel

[root@LVS1 ~]#tar -zxvf pycrypto-2.6.1.tar.gz#https://pypi.python.org/pypi/pycrypto

[root@LVS1 ~]#cd pycrypto-2.6.1

[root@LVS1 pycrypto-2.6.1]#python setup.py install

[root@LVS1 ~]#tar -zxvf paramiko-1.10.1.tar.gz#https://pypi.python.org/pypi/paramiko

[root@LVS1 ~]#cd paramiko-1.10.1

[root@LVS1 paramiko-1.10.1]# python setup.py install

[root@LVS1 demos]# python demo.py 192.168.1.10#测试

#############################################################安装django

[root@LVS1 python]# tar -zxvf Django-1.5.1.tar.gz

[root@LVS1 python]# cd Django-1.5.1

[root@LVS1 Django-1.5.1]# python setup.py install

[root@LVS1 Django-1.5.1]# cd django/bin/

[root@LVS1 bin]# ./django-admin.py startproject myweb

[root@LVS1 bin]# cd myweb

[root@LVS1 bin]# service iptables stop

[root@LVS1 myweb]# ./manage.py runserver 0.0.0.0:8000

#http://192.168.1.10:8000/

#############################################################安装python-MySQLdb

#yum install mysql-server

#service  mysqld start

#chkconfig --level 345 mysqld on

#[root@LVS1 ~]# mysql -u root

#mysql>  SET PASSWORD FOR 'root'@'localhost' = PASSWORD('123456');

#mysql> show databases;

#mysql> use mysql;

#mysql> show tables;

mysql> create database Filesystem;

#mysql>quit

[root@LVS1 ~]#yum install MySQL-python

#########################################################将输出结果直接返回到页面上

[root@LVS1 bin]# cd myweb

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/myweb

vi view.py

from django.http import HttpResponse

import datetime,time,os

def hello(request):

        return HttpResponse('hello my name is xk')

def current_time(request):

        now=datetime.datetime.now()

        html="It is now :%s"%now

        return HttpResponse(html)

def cpu(request):

        status=os.popen('top -bn 1').read()

        html="<pre>%s"%status

        return HttpResponse(html)

def hours_ahead(request,h):

        offset=int(h)

        dt=datetime.datetime.now() + datetime.timedelta(hours=offset)

        html="In %s hours later,It is %s"%(h,dt)

        return HttpResponse(html)

-------------------------------------------------

[root@LVS1 myweb]# vi urls.py

from django.conf.urls import patterns, include, url


# Uncomment the next two lines to enable the admin:

# from django.contrib import admin

# admin.autodiscover()

from myweb.view import hello,current_time,cpu,hours_ahead


urlpatterns = patterns('',

    # Examples:

    # url(r'^$', 'myweb.views.home', name='home'),

    # url(r'^myweb/', include('myweb.foo.urls')),


    # Uncomment the admin/doc line below to enable admin documentation:

    # url(r'^admin/doc/', include('django.contrib.admindocs.urls')),


    # Uncomment the next line to enable the admin:

    # url(r'^admin/', include(admin.site.urls)),

      (r'^hello/$',hello),

        (r'^time/$',current_time),

        (r'^cpu/$',cpu),

        (r'^time/plus/(\d{1,2})/$',hours_ahead),

)


#http://192.168.1.10:8000/hello/

http://192.168.1.10:8000/time/

http://192.168.1.10:8000/cpu/

http://192.168.1.10:8000/time/plus/2/#返回当前时间加上2小时之后的时间

#########################################################利用模板显示输出结果到页面上

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/myweb

[root@LVS1 myweb]# tail -2000 view2.py

from django.shortcuts import render_to_response

import os

import paramiko

hosts=['192.168.1.10','192.168.1.10','192.168.1.11','192.168.1.10','192.168.1.11','192.168.1.13']

username='root'

password='123456'

port=22

d_usage={}

d_usage2={}

def disk(request):

        i=0

        for hostname in hosts:

                i=i+1

                if os.system('ping %s -c 1'%hostname)==0:

                        paramiko.util.log_to_file('paramiko.log')

                        s = paramiko.SSHClient()

                        s.set_missing_host_key_policy(paramiko.AutoAddPolicy())

                        s.connect(hostname,port,username,password)

                        stdin,stdout,stderr=s.exec_command('df -kP')

                        d_usage[hostname+'__%s'%i]= stdout.read()

                        s.close()

                else:

                        d_usage2[hostname+'__%s'%i]='host Destination Host Unreachable'

                        name={'xk':[25,'male'],'zq':[23,'male'],}

        sum1=len(d_usage)

        sum2=len(d_usage2)

        sum=sum1+sum2

        return render_to_response('disk.html',{"d_usage":d_usage,'name':name,'sum':sum,'d_usage2':d_usage2,})

------------------------------------------------------------

[root@LVS1 myweb]# vi urls.py

from django.conf.urls import patterns, include, url


# Uncomment the next two lines to enable the admin:

# from django.contrib import admin

# admin.autodiscover()

from myweb.view2 import disk


urlpatterns = patterns('',

    # Examples:

    # url(r'^$', 'myweb.views.home', name='home'),

    # url(r'^myweb/', include('myweb.foo.urls')),


    # Uncomment the admin/doc line below to enable admin documentation:

    # url(r'^admin/doc/', include('django.contrib.admindocs.urls')),


    # Uncomment the next line to enable the admin:

    # url(r'^admin/', include(admin.site.urls)),

(r'^disk/$',disk),

)


------------------------------------------------------------

[root@LVS1 myweb]#mkdir templates

[root@LVS1 myweb]#vi /tmp/python/Django-1.5.1/django/bin/myweb/myweb/settings.py

TEMPLATE_DIRS = (

    # Put strings here, like "/home/html/django_templates" or "C:/www/django/templates".

    # Always use forward slashes, even on Windows.

    # Don't forget to use absolute paths, not relative paths.

    '/tmp/python/Django-1.5.1/django/bin/myweb/myweb/templates',

[root@LVS1 templates]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/myweb/templates

[root@LVS1 templates]# tail -1000 disk.html

<html>

<body>

<center> show disk usage</center></br>

hosts:sum-- `sum`</br>

{%for line in d_usage2.keys%}

     <font color=red>   `line`;</font>

{%endfor%}</br>

{%for line in d_usage.keys%}

        `line`;

{%endfor%}</br></br></br></br>

{% for ip,value in d_usage2.items %}

---------------------------------host`ip`----------------------------------

<font color=red><pre>   `value`</pre></font>


{% endfor %}

{% for ip,value in d_usage.items %}

---------------------------------host`ip`----------------------------------

<pre>   `value`</pre>


{% endfor %}

-----------------------------------------------------------------------------</br>

        `name`

</body>

</html>

####################################将主机文件系统、内存情况,cpu空闲率记录到MySQL数据库中

#注:先在MySQL数据库中创建好名为python的数据库,并赋给用户权限和密码

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/myweb

[root@LVS1 myweb]# vi settings.py

DATABASES = {

    'default': {

        'ENGINE': 'django.db.backends.mysql', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.

        'NAME': 'Filesystem',                      # Or path to database file if using sqlite3.

        # The following settings are not used with sqlite3:

        'USER': 'root',

        'PASSWORD': '123456',

        'HOST': '',                      # Empty for localhost through domain sockets or '127.0.0.1' for localhost through TC

P.

        'PORT': '',                      # Set to empty string for default.

    }

}

INSTALLED_APPS = (

    'django.contrib.auth',

    'django.contrib.contenttypes',

    'django.contrib.sessions',

    'django.contrib.sites',

    'django.contrib.messages',

    'django.contrib.staticfiles',

    # Uncomment the next line to enable the admin:

     'django.contrib.admin',

    # Uncomment the next line to enable admin documentation:

    # 'django.contrib.admindocs',

        'pyweb'

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb

[root@LVS1 myweb]# ./manage.py startapp pyweb

[root@LVS1 pyweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/pyweb

[root@LVS1 pyweb]# tail -2000 models.py

from django.db import models


# Create your models here.

from django.db import models


class Filesystem(models.Model):

    ip = models.CharField(max_length=30)

    date_time = models.CharField(max_length=50)

    Filesystem = models.CharField(max_length=120)

    sum_kb = models.CharField(max_length=60)

    Used = models.CharField(max_length=30)

    Available = models.CharField(max_length=50)

    Capacity = models.CharField(max_length=60)

    Mounted_on = models.CharField(max_length=60)

    def __unicode__(self):

        return self.ip

class Men_Cpu(models.Model):

        ip = models.CharField(max_length=30)

        date_time = models.CharField(max_length=50)

        Men_sum_kb = models.CharField(max_length=40)

        Men_used = models.CharField(max_length=40)

        Men_free = models.CharField(max_length=40)

        Men_idle = models.CharField(max_length=40)

        Cpu_idle = models.CharField(max_length=40)

        def __unicode__(self):

            return self.ip

class Tablespace(models.Model):

    ip = models.CharField(max_length=30)

    date_time = models.CharField(max_length=50)

    

    TABLESPACE_NAME = models.CharField(max_length=120)

    SUMMARY = models.CharField(max_length=60)

    FREE = models.CharField(max_length=30)

    MAX_FREE_EXTENT = models.CharField(max_length=50)

    FREE_EXTENTS = models.CharField(max_length=60)

    USED = models.CharField(max_length=60)

    def __unicode__(self):

        return self.ip


#class Book(models.Model):

#    title = models.CharField(max_length=100)

#    authors = models.ManyToManyField(Author)

#    publisher = models.ForeignKey(Publisher)

#    publication_date = models.DateField()

#    country = models.CharField(defau="CN",max_length=50)#默认值为CN

#    def __unicode__(self):

#        return self.title

[root@LVS1 pyweb]# 

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb

[root@LVS1 myweb]# python manage.py validate

0 errors found

[root@LVS1 myweb]# python manage.py sqlall pyweb

[root@LVS1 myweb]# python manage.py syncdb

---------------------------------------------------web站点管理上面的数据库

[root@LVS1 myweb]# pwd

/tmp/python/Django-1.5.1/django/bin/myweb/myweb

[root@LVS1 myweb]# vi settings.py

INSTALLED_APPS = (

    'django.contrib.auth',

    'django.contrib.contenttypes',

    'django.contrib.sessions',

    'django.contrib.sites',

    'django.contrib.messages',

    'django.contrib.staticfiles',

    # Uncomment the next line to enable the admin:

     'django.contrib.admin',

    # Uncomment the next line to enable admin documentation:

    # 'django.contrib.admindocs',

        'pyweb'

)

[root@LVS1 myweb]# vi urls.py

from django.conf.urls import patterns, include, url


# Uncomment the next two lines to enable the admin:

from django.contrib import admin

admin.autodiscover()



urlpatterns = patterns('',

    # Examples:

    # url(r'^$', 'myweb.views.home', name='home'),

    # url(r'^myweb/', include('myweb.foo.urls')),


    # Uncomment the admin/doc line below to enable admin documentation:

    # url(r'^admin/doc/', include('django.contrib.admindocs.urls')),


    # Uncomment the next line to enable the admin:

     url(r'^admin/', include(admin.site.urls)),

       # (r'^disk/$',disk),

)


[root@LVS1 pyweb]# tail -2000 admin.py

from django.contrib import admin

from pyweb.models import Filesystem,Men_Cpu,Tablespace 

class Filesystem_adin(admin.ModelAdmin):

        list_display=('ip','date_time','Filesystem','sum_kb','Used','Available','Capacity','Mounted_on')

        list_filter=('ip','date_time',)

        search_fields=('ip','date_time','Filesystem')

        ordering=('-date_time',)



class Men_Cpu_admin(admin.ModelAdmin):

        list_display=('ip','date_time','Men_sum_kb','Men_used','Men_free','Men_idle','Cpu_idle')

        list_filter=('ip','date_time',)

        search_fields=('ip','date_time',)

        ordering=('-date_time',)


class Tablespace_admin(admin.ModelAdmin):

        list_display=('ip','date_time','TABLESPACE_NAME','SUMMARY','FREE','MAX_FREE_EXTENT','FREE_EXTENTS','USED')

        list_filter=('ip','date_time',)

        search_fields=('ip','date_time','TABLESPACE_NAME')

        ordering=('-date_time',)


admin.site.register(Filesystem,Filesystem_adin)

admin.site.register(Men_Cpu,Men_Cpu_admin)

admin.site.register(Tablespace,Tablespace_admin)


#admin.site.register(Author)

#admin.site.register(Book)


[root@LVS1 myweb]# ./manage.py syncdb

[root@LVS1 myweb]#echo "python /tmp/python/Django-1.5.1/django/bin/myweb/manage.py runserver 0.0.0.0:8000  &>/tmp/dgangomyweb.txt &">>/etc/rc.local

http://192.168.1.10:8000/admin/#用户名和密码为第一次执行python manage.py syncdb时创建的

------------------------创建脚本(将主机文件系统、内存情况,cpu空闲率记录到MySQL数据库中)

[root@LVS1 pyweb]# tail -2000 /tmp/python/alldjango-mysql.py

#!/bin/usr/bin python

import os,datetime,paramiko

import tab,sys,multiprocessing,time

sys.path.append('/tmp/python/Django-1.5.1/django/bin/myweb')

os.environ['DJANGO_SETTINGS_MODULE'] = 'myweb.settings' 

from pyweb.models import Filesystem,Men_Cpu,Tablespace

#hosts=['192.168.1.10','192.168.1.11','192.168.1.13','192.168.1.200','192.168.1.11']

hosts=['192.168.1.10','192.168.1.11','192.168.1.13','192.168.1.10','192.168.1.200']

username='root'

password='123456'

port=22

time=datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

def run_cmd(ip):

        list=[]

        list0=[]

#       if os.system('ping %s -c 1 &>/dev/null'%ip)==0:

        try:

                        paramiko.util.log_to_file('paramiko.log')

                        s = paramiko.SSHClient()

                        s.set_missing_host_key_policy(paramiko.AutoAddPolicy())

                        s.connect(ip,port,username,password)

                        stdin,stdout,stderr=s.exec_command('df -kP')

                        df= stdout.read().split('\n')

                        stdin,stdout,stderr=s.exec_command("free|grep Mem|awk '{print $2}'")

                        list.append(stdout.read().strip())

                        stdin,stdout,stderr=s.exec_command("free|grep 'buffers/'|awk '{print $3}'")

                        list.append(stdout.read().strip())

                        stdin,stdout,stderr=s.exec_command("free|grep 'buffers/'|awk '{print $4}'")

                        list.append(stdout.read().strip())

                        list.append('%s'%(float(list[2])/float(list[0])))

                        stdin,stdout,stderr=s.exec_command("vmstat 1 2|sed -n '4p'|awk '{print $(NF-2)}'")

                        list.append(stdout.read().strip())


                        try:

                                stdin,stdout,stderr=s.exec_command('sh /tmp/tablespace.sh')

                                list0=stdout.read().split('\n')

                                list0.pop(0)

                                list0.pop(0)

                                list0.pop(0)

                                list0.pop(-1)

                        except:

                                list0=['null  null  null  null  null   null']



                        s.close()

                        print 'xxxx',ip

#       else:

        except:

                list=['null','null','null','null','null']

                df= 'nul \n null null null  null null null \n'.split('\n')

                list0=['null  null  null  null  null   null']

                print 'butong',ip

        #time=datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

        df.pop(0)

        df.pop(-1)

        for line in df:

               

               list00=line.split()

               p1 = Filesystem(ip='%s'%ip,date_time='%s'%time,Filesystem='%s'%list00[0], sum_kb='%s'%list00[1],Used='%s'%list00[2], Available='%s'%list00[3], Capacity='%s'%list00[4],Mounted_on='%s'%list00[5])

               p1.save()


        p2 = Men_Cpu(ip='%s'%ip,date_time='%s'%time,Men_sum_kb='%s'%list[0], Men_used='%s'%list[1],Men_free='%s'%list[2], Men_idle='%s'%list[3], Cpu_idle='%s'%list[4])

        p2.save()


        for list in list0:

                list=list.split()

                p3 = Tablespace(ip='%s'%ip,date_time='%s'%time,TABLESPACE_NAME='%s'%list[0], SUMMARY='%s'%list[1],FREE='%s'%list[2], MAX_FREE_EXTENT='%s'%list[3], FREE_EXTENTS='%s'%list[4],USED='%s'%list[5])

                p3.save()


p=multiprocessing.Pool(processes=10)

for hostname in hosts:

        p.apply_async(run_cmd,('%s'%hostname,))

        print hostname

#time.sleep(240)

print len(hosts)

time2=datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

print time2

p.close()

p.join()

time3=datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')

print time2

print time3

[root@LVS1 pyweb]# 

[root@LVS1 pyweb]# crontab -l

*/10 * * * * python /tmp/python/alldjango-mysql.py #每10分钟一次将主机文件系统、内存情况,cpu空闲率记录到MySQL数据库中


------------------------------------附:在装有oracle数据库的远程主机上创建查询表空间的脚本

[root@redhata ~]# vi /tmp/tablespace.sh 

#!/bin/bash

export PATH=/u01/app/oracle/product/11.2.0/dbhome_1/bin:$PATH

export ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1/

sqlplus -S /nolog <<eof

conn system/123456@orcl

set line 200;

set feedback off;

set pagesize 50000;

col member for a45;

select a.tablespace_name,a.summary,b.free,b.maxf "MAX_FREE_EXTENT",b.free_exts "FREE_EXTENTS",

    100-b.free/a.summary*100 "USED%"

        from

           (select tablespace_name,sum(bytes/1024/1024) "SUMMARY" from dba_data_files

               group by tablespace_name) a,

                   (select tablespace_name,sum(bytes/1024/1024) "FREE",max(bytes/1024/1024)

                      "MAXF" ,count(*) free_exts

                          from dba_free_space group by tablespace_name) b

                              where a.tablespace_name=b.tablespace_name

                                 order by 6 desc;

eof

                                 exit;

##########################################################################################

vi  /tmp/python/Django-1.5.1/django/bin/myweb/myweb/settings.py #修改时区

TIME_ZONE = 'Aisa/Shanghai'

#########################################################################

Django-1.5.1版本

vi /usr/lib/python2.6/site-packages/django/contrib/admin/templates/admin/base_site.html

{% extends "admin/base.html" %}

{% load i18n %}


{% block title %}` title ` | {% trans '主机性能记录系统' %}{% endblock %}


{% block branding %}

<h1 id="site-name">{% trans '主机性能记录系统' %}</h1>

{% endblock %}


{% block nav-global %}{% endblock %}

------------------------------------------------------

Django-1.9.13版本

python -c "import sys;sys.path=sys.path[1:];import django;print(django.__path__)"#找到源文件目录

cd /usr/local/lib/python3.6/site-packages/Django-1.9.13-py3.6.egg/django/contrib/admin

vi sites.py

class AdminSite(object):

    """

    An AdminSite object encapsulates an instance of the Django admin application, ready

    to be hooked in to your URLconf. Models are registered with the AdminSite using the

    register() method, and the get_urls() method can then be used to access Django view

    functions that present a full admin interface for the collection of registered

    models.

    """


    # Text to put at the end of each page's <title>.

    site_title = ugettext_lazy('配置管理系统')

    #site_title = ugettext_lazy('Django site admin')


    # Text to put in each page's <h1>.

    site_header = ugettext_lazy('配置管理系统')

    #site_header = ugettext_lazy('Django administration')


    # Text to put at the top of the admin index page.

    index_title = ugettext_lazy('配置管理系统')

    #index_title = ugettext_lazy('Site administration')


    # URL for the "View site" link at the top of each admin page.


#####################################################

[root@LVS1 myweb# pwd

/tmp/python/Django-1.5.1/django/bin/myweb

[root@LVS1 myweb]# ./manage.py shell

In [2]: from pyweb.models import Publisher

In [3]: p1 = Publisher(name='shanghai', address='24242 chuansha road',city='ShangHai', state_province='CN', country='China',website='http://www.xxk.com/')                        

In [4]: p1.save()


In [5]: p1.name='hefei'

In [6]: p1.save()

##################################################################

echo "python /tmp/python/Django-1.5.1/django/bin/myweb/manage.py runserver 0.0.0.0:8000 &>/tmp/dgangomyweb.txt &"  >>/etc/rc.local#开机启动















本文转自shangshanyang51CTO博客,原文链接:http://blog.51cto.com/qqran/1965836 ,如需转载请自行联系原作者



相关实践学习
基于CentOS快速搭建LAMP环境
本教程介绍如何搭建LAMP环境,其中LAMP分别代表Linux、Apache、MySQL和PHP。
全面了解阿里云能为你做什么
阿里云在全球各地部署高效节能的绿色数据中心,利用清洁计算为万物互联的新世界提供源源不断的能源动力,目前开服的区域包括中国(华北、华东、华南、香港)、新加坡、美国(美东、美西)、欧洲、中东、澳大利亚、日本。目前阿里云的产品涵盖弹性计算、数据库、存储与CDN、分析与搜索、云通信、网络、管理与监控、应用服务、互联网中间件、移动服务、视频服务等。通过本课程,来了解阿里云能够为你的业务带来哪些帮助 &nbsp; &nbsp; 相关的阿里云产品:云服务器ECS 云服务器 ECS(Elastic Compute Service)是一种弹性可伸缩的计算服务,助您降低 IT 成本,提升运维效率,使您更专注于核心业务创新。产品详情: https://www.aliyun.com/product/ecs
相关文章
|
18天前
|
缓存 NoSQL 关系型数据库
在Python Web开发过程中:数据库与缓存,MySQL和NoSQL数据库的主要差异是什么?
MySQL是关系型DB,依赖预定义的表格结构,适合结构化数据和复杂查询,但扩展性有限。NoSQL提供灵活的非结构化数据存储(如JSON),无统一查询语言,但能横向扩展,适用于大规模、高并发场景。选择取决于应用需求和扩展策略。
110 1
|
26天前
|
XML 关系型数据库 MySQL
python将word(doc或docx)的内容导入mysql数据库
用python先把doc文件转换成docx文件(这一步也可以不要后续会说明),然后读取docx的文件并另存为htm格式的文件(上一步可以直接把doc文件另存为htm),python根据bs4获取p标签里的内容,如果段落中有图片则保存图片。(图片在word文档中的位置可以很好的还原到生成的数据库内容) 我见网上有把docx压缩后解压获取图片的,然后根据在根据xml来读取图片的位置,我觉得比较繁琐。用docx模块读取段落的时候还需要是不是判断段落中有分页等,然而转成htm之后就不用判断那么多直接判断段落里的样式或者图片等就可以了。
19 1
|
6天前
|
安全 数据库 C++
Python Web框架比较:Django vs Flask vs Pyramid
【4月更文挑战第9天】本文对比了Python三大Web框架Django、Flask和Pyramid。Django功能全面,适合快速开发,但学习曲线较陡;Flask轻量灵活,易于入门,但默认配置简单,需自行添加功能;Pyramid兼顾灵活性和可扩展性,适合不同规模项目,但社区及资源相对较少。选择框架应考虑项目需求和开发者偏好。
|
12天前
|
存储 关系型数据库 MySQL
MySQL数据库性能大揭秘:表设计优化的高效策略(优化数据类型、增加冗余字段、拆分表以及使用非空约束)
MySQL数据库性能大揭秘:表设计优化的高效策略(优化数据类型、增加冗余字段、拆分表以及使用非空约束)
|
12天前
|
缓存 关系型数据库 MySQL
MySQL查询优化:提速查询效率的13大秘籍(合理使用索引合并、优化配置参数、使用分区优化性能、避免不必要的排序和group by操作)(下)
MySQL查询优化:提速查询效率的13大秘籍(合理使用索引合并、优化配置参数、使用分区优化性能、避免不必要的排序和group by操作)(下)
|
26天前
|
SQL 关系型数据库 MySQL
python在mysql中插入或者更新null空值
这段代码是Python操作MySQL数据库的示例。它执行SQL查询从表`a_kuakao_school`中选取`id`,`university_id`和`grade`,当`university_id`大于0时按升序排列。然后遍历结果,根据`row[4]`的值决定`grade`是否为`NULL`。若不为空,`grade`被格式化为字符串;否则,设为`NULL`。接着构造UPDATE语句更新`university`表中对应`id`的`grade`值,并提交事务。重要的是,字符串`NULL`不应加引号,否则更新会失败。
17 2
|
23小时前
|
PHP
web简易开发——通过php与HTML+css+mysql实现用户的登录,注册
web简易开发——通过php与HTML+css+mysql实现用户的登录,注册
|
2天前
|
SQL 关系型数据库 数据库
Python中SQLite数据库操作详解:利用sqlite3模块
【4月更文挑战第13天】在Python编程中,SQLite数据库是一个轻量级的关系型数据库管理系统,它包含在一个单一的文件内,不需要一个单独的服务器进程或操作系统级别的配置。由于其简单易用和高效性,SQLite经常作为应用程序的本地数据库解决方案。Python的内置sqlite3模块提供了与SQLite数据库交互的接口,使得在Python中操作SQLite数据库变得非常容易。
|
3天前
|
关系型数据库 MySQL 数据库连接
Django(四):Django项目部署数据库及服务器配置详解(MySQL)
Django(四):Django项目部署数据库及服务器配置详解(MySQL)
25 11
|
13天前
|
缓存 监控 数据库
优化数据库查询性能的八大技巧
在今天的互联网时代,数据库是许多应用程序的核心组件之一。优化数据库查询性能是提升应用程序整体性能的关键。本文介绍了八种有效的技巧,帮助开发人员提高数据库查询性能,从而提升应用程序的响应速度和用户体验。