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What is the email subject length limit?
...255 is probably the most common (and more efficient) data column length in MySQL / MariaDB. Bytes are most certainly still relevant. MySQL will use 1 byte to store the length if it is less than 256, or more otherwise. Take a look at how C++ implements std::string if you think string lengths aren'...
What is the simplest SQL Query to find the second largest value?
...
I see both some SQL Server specific and some MySQL specific solutions here, so you might want to clarify which database you need. Though if I had to guess I'd say SQL Server since this is trivial in MySQL.
I also see some solutions that won't work because they fail to...
What is WEB-INF used for in a Java EE web application?
...ains all things related to the
application that aren’t in the document root of the application. The
WEB-INF node is not part of the public document tree of the
application. No file contained in the WEB-INF directory may be served
directly to a client by the container. However, the contents...
Logging uncaught exceptions in Python
...ere is the output with sys.excepthook as seen above:
$ python tb.py
ERROR:root:Unhandled exception: Traceback (most recent call last):
File "tb.py", line 11, in <module>
None()
TypeError: 'NoneType' object is not callable
Here is the output with the sys.excepthook commented out:
$ py...
Is asynchronous jdbc call possible?
... busy/blocked per concurrent request.
If the underlying database drivers (MySql?) offers a means to intercept the socket creation (see SocketFactory) then I imagine it would be possible to build an async event driven database layer on top of the JDBC api but we'd have to encapsulate the whole JDBC ...
Rails 2.3-style plugins and deprecation warnings running task in Heroku
...Engine
alias :not_silenced_initialize :initialize
def initialize(root)
ActiveSupport::Deprecation.silence{ self.send :not_silenced_initialize, root }
end
end
end
and require it in config/application.rb just after requiring Rails:
require 'rails/all'
require File.expand_path...
How to create a self-signed certificate for a domain name for development?
...n an elevated command prompt):
makecert.exe -n "CN=My Company Development Root CA,O=My Company,
OU=Development,L=Wallkill,S=NY,C=US" -pe -ss Root -sr LocalMachine
-sky exchange -m 120 -a sha1 -len 2048 -r
You can then create a certificate bound to your subdomain and signed by your new authority...
How to add images to README.md on GitHub?
...ich for me is just the name of the image file because I have everything in root). I had been maintaining 2 copies of the README.md, one for local installation in /usr/share/projectname/docs, and one for github. Now, I can just use the same README.md for both since the image filenames work fine in bo...
Return rows in random order [duplicate]
...
For MySQL use ORDER BY uuid(). (...for those arriving on this page via a generic search, like me!)
– Stan James
Jan 7 '12 at 4:15
...
一文了解大数据领域创业的机会与方向 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...据告诉我们，究竟什么是大数据，大数据行业的创业机会如何，未来的创业方向又有哪些。
接触大数据，了解这个行业已经有两年多了，每天都在阅读大量的关于大数据的文献资料和技术文章。如果你要问我什么是大数据？以...