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MySQL - Get row number on select
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Swamibebop's solution works, but by taking advantage of table.* syntax, we can avoid repeating the column names of the inner select and get a simpler/shorter result:
SELECT @r := @r+1 ,
z.*
FROM(/* your original select statement goes in here */)z,
(SELECT @r:=0)y;
So ...
Rails: Default sort order for a rails model?
... would not it be more secure to do default_scope { order("#{table_name}.created_at DESC") } ?
– cyrilchampier
Mar 18 '14 at 17:46
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How do you validate a URL with a regular expression in Python?
...he result of parsing gives you a netloc or path you don't like, you could call that "invalid".
– S.Lott
Jun 29 '09 at 20:44
2
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PHP passing $_GET in linux command prompt
Say we usually access via
13 Answers
13
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Are the shift operators () arithmetic or logical in C?
...h may lead to implementation-defined behaviour if the value is not representable in the destination type.
Left Shift
The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated bits are filled with zeros. If E1 has an unsigned type, the value of the result is E1×2E2, reduced modulo o...
What is the iPad user agent?
... This answer is incorrect. From iOS 13 there is now no mention of iPad at all.
– CpnCrunch
Dec 16 '19 at 18:51
See th...
C# operator overload for `+=`?
...nguage has its own operators list, which are compiled in a special method calls, and CLR itself doesn't know anything about operators. So let's see what exactly stays behind the + and += operators.
See this simple code:
Decimal d = 10M;
d = d + 10M;
Console.WriteLine(d);
Let view the IL-code for...
How to implement the --verbose or -v option into a script?
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def verboseprint(*args):
# Print each argument separately so caller doesn't need to
# stuff everything to be printed into a single string
for arg in args:
print arg,
print
else:
verboseprint = lambda *a: None # do-nothing function
(Yes, y...
Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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What is the meaning of single and double underscore before an object name?
...at least two leading underscores, at most one trailing underscore) is textually replaced with _classname__spam, where classname is the current class name with leading underscore(s) stripped. This mangling is done without regard to the syntactic position of the identifier, so it can be used to define...