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SQL is null and = null [duplicate]
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In SQL, a comparison between a null value and any other value (including another null) using a comparison operator (eg =, !=, <, etc) will result in a null, which is considered as false for the purposes of a where clause (strictly speaking, it's "not true", rather...
Why did Rails4 drop support for “assets” group in the Gemfile
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Previously the assets group existed to avoid unintended compilation-on-demand in production. As Rails 4 doesn't behave like that anymore, it made sense to remove the asset group.
This is explained in more detail in the commit that changed that. I extracted some quotes with the actual answer.
Some ...
Why isn't textarea an input[type=“textarea”]?
...single-line fields ("text"), as they really are different types of things, and imply different issues (semantics) for client-side handling.
– Marc Andreessen, 11 October 1993
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How to upload files to server using JSP/Servlet?
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Introduction
To browse and select a file for upload you need a HTML <input type="file"> field in the form. As stated in the HTML specification you have to use the POST method and the enctype attribute of the form has to be set to "multipart/f...
How do I call setattr() on the current module?
... scope it's called at: the module's variables when called at global scope, and then it's OK to use it R/W, but the function's variables when called in a function, and then it must be treated as R/O -- the Python online docs can be a bit confusing about this specific distinction).
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Cannot set some HTTP headers when using System.Net.WebRequest
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If you need the short and technical answer go right to the last section of the answer.
If you want to know better, read it all, and i hope you'll enjoy...
I countered this problem too today, and what i discovered today is that:
the above ans...
Using CMake with GNU Make: How can I see the exact commands?
I use CMake with GNU Make and would like to see all commands exactly (for example how the compiler is executed, all the flags etc.).
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What do Clustered and Non clustered index actually mean?
I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes .
I googled and what I found was :
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Loop through each row of a range in Excel
This is one of those things that I'm sure there's a built-in function for (and I may well have been told it in the past), but I'm scratching my head to remember it.
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Python: How would you save a simple settings/config file?
...n the file format required.
ConfigParser [.ini format]
I would use the standard configparser approach unless there were compelling reasons to use a different format.
Write a file like so:
# python 2.x
# from ConfigParser import SafeConfigParser
# config = SafeConfigParser()
# python 3.x
from co...