见下文 更新 2 我按照你的建议做了:
更新:查看重要更新:
想把数据存到mysql-db
{'url': 'http://dom1', 'name': 'miller', 'name2': 'phil man', 'email-adress': 'waddehadde@hotmail.com'}
{'url': 'http://dom2', 'name': 'jonboy', 'name2': 'Josef dude', 'email-adress': 'waddehadde@hotmail.com'}
我有一个非常简单的数据集，但它非常大:大约 1 万条记录。 i-connect-to-a-mysql-database-in-python 我发现我可能可以使用 peewee
import peewee
from peewee import *
db = MySQLDatabase('jonhydb', user='john',passwd='megajonhy')
class Book(peewee.Model):
author = peewee.CharField()
title = peewee.TextField()
class Meta:
database = db
Book.create_table()
book = Book(author="me", title='Peewee is cool')
book.save()
for book in Book.filter(author="me"):
print book.title
Peewee is cool
我知道有两种方法可以做到这一点，一种是将号码存储在服务器上的文件中 另一个是在数据库中提供它，使用 MySQL 来存储它。我可以使用 PHP - 将其存储在 mysql-db 中。简单吧？但昨天我发现 Python 甚至更好。我在我的 linux-distri 上安装了 python
但这对我来说似乎太复杂了。
所以这让我想到了一个问题，有没有办法使用 MySQL 和 python peewee 或一些类似的轻量级 orm 来存储这个数据集!？
首先 - 非常感谢您的快速回答
我使用的是 opensuse 版本 13.1 mysql 数据库已准备就绪并正在运行。
首先我必须安装 peewee 和 json 当我有一些 isseus 安装 peewee - 见下文 后来我尝试安装 simplejson - 作为 json 的替代品 然后我猜 peewee 是 installabe。 - 见下文:
安装 peewee 时遇到问题
martin@linux-70ce:~>
martin@linux-70ce:~> git clone https://github.com/coleifer/peewee.git
Klone nach 'peewee'...
remote: Reusing existing pack: 5673, done.
remote: Counting objects: 13, done.
remote: Compressing objects: 100% (13/13), done.
remote: Total 5686 (delta 2), reused 0 (delta 0)
Empfange Objekte: 100% (5686/5686), 3.54 MiB | 102.00 KiB/s, done.
Löse Unterschiede auf: 100% (3468/3468), done.
Prüfe Konnektivität... Fertig
martin@linux-70ce:~> cd peewee
martin@linux-70ce:~/peewee> python setup.py install
running install
error: can't create or remove files in install directory
The following error occurred while trying to add or remove files in the
installation directory:
[Errno 13] Permission denied: '/usr/lib/python2.7/site-packages/test-easy-install-5717.write-test'
The installation directory you specified (via --install-dir, --prefix, or
the distutils default setting) was:
/usr/lib/python2.7/site-packages/
Perhaps your account does not have write access to this directory? If the
installation directory is a system-owned directory, you may need to sign in
as the administrator or "root" account. If you do not have administrative
access to this machine, you may wish to choose a different installation
directory, preferably one that is listed in your PYTHONPATH environment
variable.
For information on other options, you may wish to consult the
documentation at:
Please make the appropriate changes for your system and try again.
martin@linux-70ce:~/peewee>
之后 - 如上所述 - 我安装了 simplejson 然后我尝试再次安装 peewee::现在我想我有更多的运气....
martin@linux-70ce:~/peewee> git clone https://github.com/coleifer/peewee.git
Klone nach 'peewee'...
remote: Reusing existing pack: 5673, done.
remote: Counting objects: 13, done.
remote: Compressing objects: 100% (13/13), done.
remote: Total 5686 (delta 2), reused 0 (delta 0)
Empfange Objekte: 100% (5686/5686), 3.54 MiB | 309.00 KiB/s, done.
fix the conflicts: 100% (3468/3468), done.
Prüfe Konnektivität... Fertig
马丁@linux-70ce:~/peewee>
查看完整代码——我正在运行
import urllib
import urlparse
import re
from peewee import *
import json
db = MySQLDatabase('cpan', user='root',passwd='rimbaud')
class User(Model):
name = TextField()
cname = TextField()
email = TextField()
url = TextField()
class Meta:
database = db # this model uses the cpan database
User.create_table() #ensure table is created
url = "http://search.cpan.org/author/?W"
html = urllib.urlopen(url).read()
for lk, capname, name in re.findall('<a href="(/~.*?/)"><b>(.*?)</b></a><br/><small>(.*?)</small>', html):
alk = urlparse.urljoin(url, lk)
data = { 'url':alk, 'name':name, 'cname':capname }
phtml = urllib.urlopen(alk).read()
memail = re.search('<a href="mailto:(.*?)">', phtml)
if memail:
data['email'] = memail.group(1)
data = json.load() #your json data file here
for entry in data: #assuming your data is an array of JSON objects
user = User.create(name=entry["name"], cname=entry["cname"],
email=entry["email"], url=entry["url"])
user.save()
以及随后的结果:
martin@linux-70ce:~/perl> python cpan6.py
python: can't open file 'cpan6.py': [Errno 2] No such file or directory
martin@linux-70ce:~/perl> python cpan5.py
Traceback (most recent call last):
File "cpan5.py", line 7, in <module>
from peewee import *
ImportError: No module named peewee
martin@linux-70ce:~/perl>
好吧，现在我有点无能为力 - 很想听听你的消息 提前谢谢了!!
更新 2 我按照你的建议做了:
martin@linux-70ce:~/peewee> sudo python setup.py install
t
linux-70ce:/home/martin/perl # cd ..
linux-70ce:/home/martin # cd peewee/
linux-70ce:/home/martin/peewee # sudo python setup.py install
running install
running bdist_egg
running egg_info
creating peewee.egg-info
writing peewee.egg-info/PKG-INFO
writing top-level names to peewee.egg-info/top_level.txt
writing dependency_links to peewee.egg-info/dependency_links.txt
writing manifest file 'peewee.egg-info/SOURCES.txt'
reading manifest file 'peewee.egg-info/SOURCES.txt'
reading manifest template 'MANIFEST.in'
writing manifest file 'peewee.egg-info/SOURCES.txt'
installing library code to build/bdist.linux-i686/egg
running install_lib
running build_py
creating build
creating build/lib
copying peewee.py -> build/lib
copying pwiz.py -> build/lib
creating build/lib/playhouse
copying playhouse/tests_shortcuts.py -> build/lib/playhouse
copying playhouse/read_slave.py -> build/lib/playhouse
copying playhouse/tests_kv.py -> build/lib/playhouse
copying playhouse/tests_pwiz.py -> build/lib/playhouse
copying playhouse/gfk.py -> build/lib/playhouse
copying playhouse/test_utils.py -> build/lib/playhouse
copying playhouse/apsw_ext.py -> build/lib/playhouse
copying playhouse/__init__.py -> build/lib/playhouse
copying playhouse/tests_pool.py -> build/lib/playhouse
copying playhouse/tests_apsw.py -> build/lib/playhouse
copying playhouse/kv.py -> build/lib/playhouse
copying playhouse/postgres_ext.py -> build/lib/playhouse
copying playhouse/signals.py -> build/lib/playhouse
copying playhouse/sqlcipher_ext.py -> build/lib/playhouse
copying playhouse/tests_gfk.py -> build/lib/playhouse
copying playhouse/tests_read_slave.py -> build/lib/playhouse
copying playhouse/pool.py -> build/lib/playhouse
copying playhouse/tests_csv_loader.py -> build/lib/playhouse
copying playhouse/tests_berkeleydb.py -> build/lib/playhouse
copying playhouse/djpeewee.py -> build/lib/playhouse
copying playhouse/tests_test_utils.py -> build/lib/playhouse
copying playhouse/migrate.py -> build/lib/playhouse
copying playhouse/csv_loader.py -> build/lib/playhouse
copying playhouse/tests_postgres.py -> build/lib/playhouse
copying playhouse/tests_migrate.py -> build/lib/playhouse
copying playhouse/tests_djpeewee.py -> build/lib/playhouse
copying playhouse/tests_sqlite_ext.py -> build/lib/playhouse
copying playhouse/berkeleydb.py -> build/lib/playhouse
copying playhouse/proxy.py -> build/lib/playhouse
copying playhouse/tests_signals.py -> build/lib/playhouse
copying playhouse/sqlite_ext.py -> build/lib/playhouse
copying playhouse/tests_sqlcipher_ext.py -> build/lib/playhouse
copying playhouse/shortcuts.py -> build/lib/playhouse
creating build/bdist.linux-i686
creating build/bdist.linux-i686/egg
copying build/lib/peewee.py -> build/bdist.linux-i686/egg
creating build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_shortcuts.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/read_slave.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_kv.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_pwiz.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/gfk.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/test_utils.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/apsw_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/__init__.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_pool.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_apsw.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/kv.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/postgres_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/signals.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/sqlcipher_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_gfk.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_read_slave.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/pool.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_csv_loader.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_berkeleydb.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/djpeewee.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_test_utils.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/migrate.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/csv_loader.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_postgres.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_migrate.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_djpeewee.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_sqlite_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/berkeleydb.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/proxy.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_signals.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/sqlite_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/tests_sqlcipher_ext.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/playhouse/shortcuts.py -> build/bdist.linux-i686/egg/playhouse
copying build/lib/pwiz.py -> build/bdist.linux-i686/egg
byte-compiling build/bdist.linux-i686/egg/peewee.py to peewee.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_shortcuts.py to tests_shortcuts.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/read_slave.py to read_slave.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_kv.py to tests_kv.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_pwiz.py to tests_pwiz.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/gfk.py to gfk.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/test_utils.py to test_utils.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/apsw_ext.py to apsw_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/__init__.py to __init__.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_pool.py to tests_pool.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_apsw.py to tests_apsw.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/kv.py to kv.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/postgres_ext.py to postgres_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/signals.py to signals.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/sqlcipher_ext.py to sqlcipher_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_gfk.py to tests_gfk.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_read_slave.py to tests_read_slave.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/pool.py to pool.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_csv_loader.py to tests_csv_loader.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_berkeleydb.py to tests_berkeleydb.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/djpeewee.py to djpeewee.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_test_utils.py to tests_test_utils.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/migrate.py to migrate.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/csv_loader.py to csv_loader.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_postgres.py to tests_postgres.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_migrate.py to tests_migrate.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_djpeewee.py to tests_djpeewee.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_sqlite_ext.py to tests_sqlite_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/berkeleydb.py to berkeleydb.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/proxy.py to proxy.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_signals.py to tests_signals.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/sqlite_ext.py to sqlite_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/tests_sqlcipher_ext.py to tests_sqlcipher_ext.pyc
byte-compiling build/bdist.linux-i686/egg/playhouse/shortcuts.py to shortcuts.pyc
byte-compiling build/bdist.linux-i686/egg/pwiz.py to pwiz.pyc
creating build/bdist.linux-i686/egg/EGG-INFO
installing scripts to build/bdist.linux-i686/egg/EGG-INFO/scripts
running install_scripts
running build_scripts
creating build/scripts-2.7
copying and adjusting pwiz.py -> build/scripts-2.7
changing mode of build/scripts-2.7/pwiz.py from 644 to 755
creating build/bdist.linux-i686/egg/EGG-INFO/scripts
copying build/scripts-2.7/pwiz.py -> build/bdist.linux-i686/egg/EGG-INFO/scripts
changing mode of build/bdist.linux-i686/egg/EGG-INFO/scripts/pwiz.py to 755
copying peewee.egg-info/PKG-INFO -> build/bdist.linux-i686/egg/EGG-INFO
copying peewee.egg-info/SOURCES.txt -> build/bdist.linux-i686/egg/EGG-INFO
copying peewee.egg-info/dependency_links.txt -> build/bdist.linux-i686/egg/EGG-INFO
copying peewee.egg-info/top_level.txt -> build/bdist.linux-i686/egg/EGG-INFO
zip_safe flag not set; analyzing archive contents...
creating dist
creating 'dist/peewee-2.2.5-py2.7.egg' and adding 'build/bdist.linux-i686/egg' to it
removing 'build/bdist.linux-i686/egg' (and everything under it)
Processing peewee-2.2.5-py2.7.egg
Copying peewee-2.2.5-py2.7.egg to /usr/lib/python2.7/site-packages
Adding peewee 2.2.5 to easy-install.pth file
Installing pwiz.py script to /usr/bin
Installed /usr/lib/python2.7/site-packages/peewee-2.2.5-py2.7.egg
Processing dependencies for peewee==2.2.5
Finished processing dependencies for peewee==2.2.5
linux-70ce:/home/martin/peewee #
查看最新更新 - 正确安装 peewee 后，我运行脚本，现在看看发生了什么。
import urllib
import urlparse
import re
import peewee
import json
db = MySQLDatabase('cpan', user='root',passwd='rimbaud')
class User(Model):
name = TextField()
cname = TextField()
email = TextField()
url = TextField()
class Meta:
database = db # this model uses the cpan database
User.create_table() #ensure table is created
url = "http://search.cpan.org/author/?W"
html = urllib.urlopen(url).read()
for lk, capname, name in re.findall('<a href="(/~.*?/)"><b>(.*?)</b></a><br/><small>(.*?)</small>', html):
alk = urlparse.urljoin(url, lk)
data = { 'url':alk, 'name':name, 'cname':capname }
phtml = urllib.urlopen(alk).read()
memail = re.search('<a href="mailto:(.*?)">', phtml)
if memail:
data['email'] = memail.group(1)
data = json.load() #your json data file here
for entry in data: #assuming your data is an array of JSON objects
user = User.create(name=entry["name"], cname=entry["cname"],
email=entry["email"], url=entry["url"])
user.save()
我找回了这个错误。
Traceback (most recent call last):
File "cpan5.py", line 10, in <module>
db = MySQLDatabase('cpan', user='root',passwd='rimbaud')
NameError: name 'MySQLDatabase' is not defined
linux-70ce:/home/martin/perl #
最新更新:从 7 月 14 日开始
假设现在一切正常 - 我已经设置好了...所以 好吧 - 但它在某个时候失败了。
import urllib
import urlparse
import re
# import peewee
import json
from peewee import *
#from peewee import MySQLDatabase ('cpan', user='root',passwd='rimbaud')
db = MySQLDatabase('cpan', user='root',passwd='rimbaud')
class User(Model):
name = TextField()
cname = TextField()
email = TextField()
url = TextField()
class Meta:
database = db # this model uses the cpan database
User.create_table() #ensure table is created
url = "http://search.cpan.org/author/?W"
html = urllib.urlopen(url).read()
for lk, capname, name in re.findall('<a href="(/~.*?/)"><b>(.*?)</b></a><br/><small>(.*?)</small>', html):
alk = urlparse.urljoin(url, lk)
data = { 'url':alk, 'name':name, 'cname':capname }
phtml = urllib.urlopen(alk).read()
memail = re.search('<a href="mailto:(.*?)">', phtml)
if memail:
data['email'] = memail.group(1)
data = json.load('email') #your json data file here
for entry in data: #assuming your data is an array of JSON objects
user = User.create(name=entry["name"], cname=entry["cname"],
email=entry["email"], url=entry["url"])
user.save()
猜测必须存在一个数据文件:一个在解析过程中由脚本创建的...对吗？
)
martin@linux-70ce:~/perl> python cpan_100.py
Traceback (most recent call last):
File "cpan_100.py", line 47, in <module>
data = json.load('email') #your json data file here
File "/usr/lib/python2.7/json/__init__.py", line 286, in load
return loads(fp.read(),
AttributeError: 'str' object has no attribute 'read'
martin@linux-70ce:~/perl>
很高兴收到你的来信
最佳答案
假设你想使用 python 和 peewee，我会做类似下面的事情:
from peewee import *
import json
db = MySQLDatabase('jonhydb', user='john',passwd='megajonhy')
class User(Model):
name = TextField()
name2 = TextField()
email_address = TextField()
url = TextField()
class Meta:
database = db # this model uses the jonhydb database
User.create_table() #ensure table is created
data = json.load() #your json data file here
for entry in data: #assuming your data is an array of JSON objects
user = User.create(name=entry["name"], name2=entry["name2"],
email_address=entry["email-adress"], url=entry["url"])
user.save()
关于php - 在 mysql 中存储 10000 行的 python 字典 - 而不是打印，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24635811/
关闭。这个问题是opinion-based.它目前不接受答案。想要改进这个问题？更新问题，以便editingthispost可以用事实和引用来回答它.关闭4年前。Improvethisquestion我想在固定时间创建一系列低音和高音调的哔哔声。例如:在150毫秒时发出高音调的蜂鸣声在151毫秒时发出低音调的蜂鸣声200毫秒时发出低音调的蜂鸣声250毫秒的高音调蜂鸣声有没有办法在Ruby或Python中做到这一点？我真的不在乎输出编码是什么(.wav、.mp3、.ogg等等)，但我确实想创建一个输出文件。
我主要使用Ruby来执行此操作，但到目前为止我的攻击计划如下:使用gemsrdf、rdf-rdfa和rdf-microdata或mida来解析给定任何URI的数据。我认为最好映射到像schema.org这样的统一模式，例如使用这个yaml文件，它试图描述数据词汇表和opengraph到schema.org之间的转换:#SchemaXtoschema.orgconversion#data-vocabularyDV:name:namestreet-address:streetAddressregion:addressRegionlocality:addressLocalityphoto:i
我将应用程序升级到Rails4，一切正常。我可以登录并转到我的编辑页面。也更新了观点。使用标准View时，用户会更新。但是当我添加例如字段:name时，它不会在表单中更新。使用devise3.1.1和gem'protected_attributes'我需要在设备或数据库上运行某种更新命令吗？我也搜索过这个地方，找到了许多不同的解决方案，但没有一个会更新我的用户字段。我没有添加任何自定义字段。 最佳答案 如果您想允许额外的参数，您可以在ApplicationController中使用beforefilter，因为Rails4将参数
这个问题在这里已经有了答案:关闭10年前。PossibleDuplicate:Pythonconditionalassignmentoperator对于这样一个简单的问题表示歉意，但是谷歌搜索||=并不是很有帮助；)Python中是否有与Ruby和Perl中的||=语句等效的语句？例如:foo="hey"foo||="what"#assignfooifit'sundefined#fooisstill"hey"bar||="yeah"#baris"yeah"另外，类似这样的东西的通用术语是什么？条件分配是我的第一个猜测，但Wikipediapage跟我想的不太一样。
什么是ruby的rack或python的Java的wsgi？还有一个路由库。 最佳答案 来自Python标准PEP333:Bycontrast,althoughJavahasjustasmanywebapplicationframeworksavailable,Java's"servlet"APImakesitpossibleforapplicationswrittenwithanyJavawebapplicationframeworktoruninanywebserverthatsupportstheservletAPI.ht
我正在编写一个简单的静态Rack应用程序。查看下面的config.ru代码:useRack::Static,:urls=>["/elements","/img","/pages","/users","/css","/js"],:root=>"archive"map'/'dorunProc.new{|env|[200,{'Content-Type'=>'text/html','Cache-Control'=>'public,max-age=6400'},File.open('archive/splash.html',File::RDONLY)]}endmap'/pages/search.
华为OD机试题本篇题目：明明的随机数题目输入描述输出描述：示例1输入输出说明代码编写思路最近更新的博客华为od2023|什么是华为od，od薪资待遇，od机试题清单华为OD机试真题大全，用Python解华为机试题|机试宝典【华为OD机试】全流程解析+经验分享,题型分享,防作弊指南华为o
文章目录一、概述简介原理模块二、配置Mysql使用版本环境要求1.操作系统2.mysql要求三、配置canal-server离线下载在线下载上传解压修改配置单机配置集群配置分库分表配置1.修改全局配置2.实例配置垂直分库水平分库3.修改group-instance.xml4.启动监听四、配置canal-adapter1修改启动配置2配置映射文件3启动ES数据同步查询所有订阅同步数据同步开关启动4.验证五、配置canal-admin一、概述简介canal是Alibaba旗下的一款开源项目，Java开发。基于数据库增量日志解析，提供增量数据订阅&消费。Git地址：https://github.co
HashMap中为什么引入红黑树，而不是AVL树呢1.概述开始学习这个知识点之前我们需要知道，在JDK1.8以及之前，针对HashMap有什么不同。JDK1.7的时候，HashMap的底层实现是数组+链表JDK1.8的时候，HashMap的底层实现是数组+链表+红黑树我们要思考一个问题，为什么要从链表转为红黑树呢。首先先让我们了解下链表有什么不好？？？2.链表上述的截图其实就是链表的结构，我们来看下链表的增删改查的时间复杂度增：因为链表不是线性结构，所以每次添加的时候，只需要移动一个节点，所以可以理解为复杂度是N(1)删：算法时间复杂度跟增保持一致查：既然是非线性结构，所以查询某一个节点的时候
我想解析一个已经存在的.mid文件，改变它的乐器，例如从“acousticgrandpiano”到“violin”，然后将它保存回去或作为另一个.mid文件。根据我在文档中看到的内容，该乐器通过program_change或patch_change指令进行了更改，但我找不到任何在已经存在的MIDI文件中执行此操作的库.他们似乎都只支持从头开始创建的MIDI文件。 最佳答案 MIDIpackage会为您完成此操作，但具体方法取决于midi文件的原始内容。一个MIDI文件由一个或多个音轨组成，每个音轨是十六个channel中任何一个上的