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How do I check if a SQL Server text column is empty?
...ullness and emptiness nature of a text column and accordingly assign value based on condition. Upvote for the answer since this is what I was looking for. Thanks
– user_v
Feb 3 '12 at 17:10
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Rails: Why does find(id) raise an exception in rails? [duplicate]
If there is no user with an id of 1 in the database, trying User.find(1) will raise an exception.
2 Answers
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Why would one use the Publish/Subscribe pattern (in JS/jQuery)?
...he main goal is to reduce coupling between the code. It's a somewhat event-based way of thinking, but the "events" aren't tied to a specific object.
I'll write out a big example below in some pseudo code that looks a bit like JavaScript.
Let's say we have a class Radio and a class Relay:
class Re...
jQuery: count number of rows in a table
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@DevlshOne That is not true, length is not zero base, check the documentation: api.jquery.com/length
– Miguel
May 1 '13 at 16:01
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How to add include path in Qt Creator?
...ur own build system, you create a project by selecting "Import of Makefile-based project". This will create some files in your project directory including a file named <your project name>.includes. In that file, simply list the paths you want to include, one per line. Really all this does i...
What is the meaning of the 'g' flag in regular expressions?
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Will give example based on string. If we want to remove all occurences from a
string.
Lets say if we want to remove all occurences of "o" with "" from "hello world"
"hello world".replace(/o/g,'');
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How to check if a DateTime occurs today?
...s a DateTime object
.NET is smart enough to determine you want to compare based on Date only and uses that for the internal Compare. Not sure why, and actually having trouble finding documentation for this behaviour.
share
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Extract a regular expression match
...nces in 'See also':
‘regmatches’ for extracting matched substrings based on the results of
‘regexpr’, ‘gregexpr’ and ‘regexec’.
So this will work, and is fairly simple:
txt <- "aaa12xxx"
regmatches(txt,regexpr("[0-9]+",txt))
#[1] "12"
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What is pseudopolynomial time? How does it differ from polynomial time?
...r of bits required to represent W
i.e. size of input= s =log(W) (log= log base 2)
-> 2^(s)=2^(log(W))
-> 2^(s)=W (because 2^(log(x)) = x)
Now, running time of knapsack= O(nW) = O(n * 2^s)
which is not polynomial.
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Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...or the request and a background thread (async) looping to read a file, database or whatever.
– JavierJ
Nov 30 '15 at 18:22
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