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SQL Server equivalent to MySQL enum data type?
... then you'll end-up adding lots of tables to your database. Not to mention extra IO reads due to FK constraint-checking when inserting/deleting data, whereas a CHECK CONSTRAINT is much faster and doesn't cause database object spam.
– Dai
Sep 18 at 7:23
...
How do I best silence a warning about unused variables?
...tion is more convenient, although less cleaner.
– cbuchart
Jul 17 '14 at 6:57
I think simpler is better, commenting ou...
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 ...
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) ...
Why Collections.sort uses merge sort instead of quicksort?
...ast stable sort that guarantees O(n log n)
performance and requires O(n) extra space. In its day (it was written
in 1997 by Joshua Bloch), it was a fine choice, but today but we can
do much better.
Since 2003, Python's list sort has used an algorithm known as timsort
(after Tim Peters,...
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.
&...
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?...
Detecting which UIButton was pressed in a UITableView
...)metaData:(id)target
Enjoy
#import <objc/runtime.h>
static char const * const kMetaDic = "kMetaDic";
#pragma mark - Getters / Setters
- (id)metaData:(id)target {
return objc_getAssociatedObject(target, kMetaDic);
}
- (void)setMetaData:(id)target withObject:(id)newObj {
...
What does -D_XOPEN_SOURCE do/mean?
...t;some number>
it tells your compiler to include definitions for some extra functions that are defined in the X/Open and POSIX standards.
This will give you some extra functionality that exists on most recent UNIX/BSD/Linux systems, but probably doesn't exist on other systems such as Windows.
...
How to find encoding of a file via script on Linux?
...ill output MIME-type information for the file, which will also include the character-set encoding. I found a man-page for it, too :)
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