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What's wrong with nullable columns in composite primary keys?
...n relational database design." - a null-free database design (Sixth normal form) invariably adds complexity, the space-savings gained are often outweighed by the extra programmer work needed to realise those gains.
– Dai
May 28 '16 at 13:11
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Coffeescript — How to create a self-initiating anonymous function?
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As of CoffeeScript 1.3.1 (released April 2012), do also lets you pass arguments to the function. To pass 1 and 2 as the parameters x and y, write do (x = 1, y = 2) ->. (The documentation for this feature has gotten lost, but the issue where the feature was introdu...
How to prevent browser page caching in Rails
...nse.headers["Pragma"] = "no-cache"
response.headers["Expires"] = "Mon, 01 Jan 1990 00:00:00 GMT"
end
end
Rails 4 and older versions:
class ApplicationController < ActionController::Base
before_filter :set_cache_headers
private
def set_cache_headers
response.headers["Cache-Co...
Remove file extension from a file name string
...s file path
– lemon
Oct 2 '15 at 22:01
8
This is a better answer as it preserves the path
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DateTime2 vs DateTime in SQL Server
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DATETIME2 has a date range of "0001 / 01 / 01" through "9999 / 12 / 31" while the DATETIME type only supports year 1753-9999.
Also, if you need to, DATETIME2 can be more precise in terms of time; DATETIME is limited to 3 1/3 milliseconds, while DATETIME2 ca...
HEAD and ORIG_HEAD in Git
..., ORIG_HEAD is last value of HEAD before dangerous operation).
For more information read git(1) manpage, Git User's Manual, the Git Community Book and Git Glossary
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Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
...ime.
– Tom Stickel
May 11 '17 at 20:01
1
And how would you do that? Example requests?
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Private virtual method in C++
...s that the C++ FAQ Lite has since changed its recommendation: "the C++ FAQ formerly recommended using protected virtuals rather than private virtuals. However the private virtual approach is now common enough that confusion of novices is less of a concern."
– Zack The Human
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How can I export tables to Excel from a webpage [closed]
...xport tables to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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Create the perfect JPA entity [closed]
.../ empty fields on proxy instances.
Protected is better for (Hibernate) performance?
Unlikely.
Equals/HashCode?
This is relevant to working with entities, before they've been saved -- which is a thorny issue. Hashing/comparing on immutable values? In most business applications, there aren't any.
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