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Are there disadvantages to using a generic varchar(255) for all text-based fields?
...stcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(25...
MySQL SELECT only not null values
...hough...
SELECT val1 AS val
FROM your_table
WHERE val1 IS NOT NULL
UNION ALL
SELECT val2
FROM your_table
WHERE val2 IS NOT NULL
/*And so on for all your columns*/
The disadvantage of the above is that it scans the table multiple times once for each column. That may possibly be avoided by the b...
Eventual consistency in plain English
...omorrow.
You tell your neighbor that it is going to rain tomorrow.
Eventually, all of the servers (you, me, your neighbor) know the truth (that it's going to rain tomorrow), but in the meantime the client (his wife) came away thinking it is going to be sunny, even though she asked after one or mor...
Is it possible to execute code once before all tests run?
Basically I would like to tell MSTest to execute a bit of code before launching into a series of test runs, essentially what I would like to do is the same thing as sticking some code in Main() .
...
How do I run only specific tests in Rspec?
...onfiguration option treat_symbols_as_metadata_keys_with_true_values, which allows you to do:
describe "Awesome feature", :awesome do
where :awesome is treated as if it were :awesome => true.
Also see this answer for how to configure RSpec to automatically run 'focused' tests. This works especi...
Windows 8.1 / Windows 10 breaks my ASP.NET / IIS : “Service unavailable”
With Windows 8.1 finally released to MSDN/Technet today I came across the following issue running my ASP.NET application after doing an in place upgrade with Win 8.1 RTM:
...
Importing CSV with line breaks in Excel 2007
...
@user1859022 I double that for Hungarian locale. actually any locale that uses comma as decimal separator has to use semicolon as field separator for the double-click csv open to work properly
– robotik
Jul 28 '16 at 11:53
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Define all functions in one .R file, call them from another .R file. How, if possible?
How do I call functions defined in abc.R file in another file, say xyz.R?
1 Answer
1
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Can you write virtual functions / methods in Java?
...
From wikipedia
In Java, all non-static methods are by
default "virtual functions." Only
methods marked with the keyword final,
which cannot be overridden, along with
private methods, which are not
inherited, are non-virtual.
...
What is the purpose of `text=auto` in `.gitattributes` file?
...f form:
pattern attr1 attr2 ...
So here, the pattern is *, which means all files, and the attribute is text=auto.
What does text=auto do? From the documentation:
When text is set to "auto", the path is marked for automatic end-of-line normalization. If Git decides that the content is text, ...