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Meaning of numbers in “col-md-4”,“ col-xs-1”, “col-lg-2” in Bootstrap
...ey are used to define at which screen size that class should apply:
xs = extra small screens (mobile phones)
sm = small screens (tablets)
md = medium screens (some desktops)
lg = large screens (remaining desktops)
Read the "Grid
Options"
chapter from the official Bootstrap documentation f...
What is the difference between RDF and OWL? [closed]
...edicate. The object is either another URI or a literal such as a number or string. Literals can have a type (which is also a URI), and they can also have a language. Yes, this means triples can have up to 5 bits of data!
For example a triple might describe the fact that Charles is Harrys father.
&...
Check if one IEnumerable contains all elements of another IEnumerable
...ter than the others. Thanks for the tip.
– Brandon Zacharie
Jul 18 '10 at 11:21
2
This does not w...
PostgreSQL “DESCRIBE TABLE”
...so on)
The SQL standard way, as shown here:
select column_name, data_type, character_maximum_length, column_default, is_nullable
from INFORMATION_SCHEMA.COLUMNS where table_name = '<name of table>';
It's supported by many db engines.
...
Get MIME type from filename extension
...ing.GetMimeMapping method, that is part of the BCL in .NET Framework 4.5:
string mimeType = MimeMapping.GetMimeMapping(fileName);
If you need to add custom mappings you probably can use reflection to add mappings to the BCL MimeMapping class, it uses a custom dictionary that exposes this method, ...
RequestDispatcher.forward() vs HttpServletResponse.sendRedirect()
...cted address. It’s not transparent.
sendRedirect is slower because one extra round trip is required, because a completely new request is created and the old request object is lost. Two browser request are required.
But in sendRedirect, if we want to use the same data for a new resource we have...
CHECK constraint in MySQL is not working
...GER `test_before_insert` BEFORE INSERT ON `Test`
FOR EACH ROW
BEGIN
IF CHAR_LENGTH( NEW.ID ) < 4 THEN
SIGNAL SQLSTATE '12345'
SET MESSAGE_TEXT := 'check constraint on Test.ID failed';
END IF;
END$$
DELIMITER ;
Prior to MySQL 5.5 you had to cause an error, e.g. ca...
C# Events and Thread Safety
...ith every event - aka boilerplate code!
public event Action<thisClass, string> Some;
protected virtual void DoSomeEvent(string someValue)
{
var e = Some; // avoid race condition here!
if(null != e) // avoid null condition here!
e(this, someValue);
}
2 - the race condition issue) ...
How to ignore xargs commands if stdin input is empty?
... may take advantage of -L <#lines>, -n <#args>, -i, and -I <string>:
ls /empty_dir/ | xargs -n10 chown root # chown executed every 10 args or fewer
ls /empty_dir/ | xargs -L10 chown root # chown executed every 10 lines or fewer
ls /empty_dir/ | xargs -i cp {} {}.bak # every {} is ...
In Python, what happens when you import inside of a function? [duplicate]
...me is expensive. Try running an empty script vs one containing just import string,itertools,fractions,heapq,re,array,bisect,collections,math,os. The first takes an average of 180 ms, and the second 230 ms. So it's not microseconds for starters. It's tens of milliseconds (maybe a disc access happens?...