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Can I change a column from NOT NULL to NULL without dropping it?
... I tried with alter column and it didn't work with the latest mysql server. I tried with modify column and it worked. Strange...
– Kostas Andrianos
Aug 19 '17 at 15:29
...
Exclude a directory from git diff
...s will exclude files relative to the current working directory AND the git root directory.
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Difference between string and text in rails?
...l is converted into its respective column type in query language.
with MySQL :string is mapped to VARCHAR(255)
- http://guides.rubyonrails.org/migrations.html
:string | VARCHAR | :limit => 1 to 255 (default = 255)
:text | TINYTEXT, TEXT, MEDIUMTEXT, or...
Ignore .pyc files in git repository
...in a .gitignore file in any of the directories leading from the repository root (inclusive).
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中关村服务辐射百万创业者 - 资讯 - 清泛网 - 专注C/C++及内核技术
...间、人才、资本……成为拦在创业道路上的种种难题。
如何才能在日益变化的环境下更好地帮到创业者，成为摆在创业服务业面前的最大问题。6月25日，清控科创携手清华控股、北极光创投、完美时空、银杏天使、创业邦、盛...
正则表达式 30 分钟入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...：deerchao 转载请注明来源
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PHP编译configure时常见错误 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...e gmp.h
centos: yum install gmp-devel
14、Configure: error: Cannot find MySQL header files under /usr. Note that the MySQL client library is not bundled anymore!
yum install mysql-devel (For Redhat & Fedora)
# apt-get install libmysql++-dev (For Ubuntu)
15、Configure: error: Please reinstall ...
Xcode build failure “Undefined symbols for architecture x86_64”
...ine for oAuthIOS framework. Add oAuthIOS framework from pods folder to the root project you are trying to build
– prodeveloper
Oct 30 '14 at 11:51
1
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Cannot issue data manipulation statements with executeQuery()
In MySQL I have two tables, tableA and tableB . I am trying to execute two queries:
10 Answers
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How to log something in Rails in an independent log file?
...ActiveRecord::Base
def my_logger
@@my_logger ||= Logger.new("#{Rails.root}/log/my.log")
end
def before_save
my_logger.info("Creating user with name #{self.name}")
end
end
Here I used a class attribute to memoize the logger. This way it won't be created for every single User object...