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Difference between Select Unique and Select Distinct
...
SELECT UNIQUE is old syntax supported by Oracle's flavor of SQL. It is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than ...
Is there any kind of hash code function in JavaScript?
... var hash = 0;
for (var i = 0; i < this.length; i++) {
var character = this.charCodeAt(i);
hash = ((hash<<5)-hash)+character;
hash = hash & hash; // Convert to 32bit integer
}
return hash;
}
That is the way of implementation in Java (bitwise operat...
How to express a NOT IN query with ActiveRecord/Rails?
...rums, lambda { |forums| { :conditions => ['forum_id not in (?)', forums.select(&:id).join(',')] }
# in your controller
Topic.not_in_forums(@forums)
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Can hash tables really be O(1)?
...TW - concrete example - Visual C++'s std::hash of textual keys combines 10 characters evenly spaced along the text into the hash value, so it's O(1) regardless of text length (but massively more collision prone than GCC!). Separately, claims of O(1) have another assumption (normally correctly) that...
Understanding recursion [closed]
.... We'll use a binary tree of nodes, but this time the value held will be a character, not a number.
Our tree will have a special property, that for any node, its character comes after (in alphabetical order) the character held by its left child and before (in alphabetical order) the character held ...
Why can Java Collections not directly store Primitives types?
...s. How would you write a collection that can store either int, or float or char? Most likely you will end up with multiple collections, so you will need an intlist and a charlist etc.
Taking advantage of the object oriented nature of Java when you write a collection class it can store any object so...
How to define an enumerated type (enum) in C?
...um { RANDOM, IMMEDIATE, SEARCH } strategy = IMMEDIATE;
int main(int argc, char** argv){
printf("strategy: %d\n", strategy);
return 0;
}
If instead of the above, the second line were changed to:
...
enum { RANDOM, IMMEDIATE, SEARCH } strategy;
strategy = IMMEDIATE;
...
From the warnings, ...
Remove Last Comma from a string
...cript, how can I remove the last comma, but only if the comma is the last character or if there is only white space after the comma? This is my code.
I got a working fiddle . But it has a bug.
...
Problem with converting int to string in Linq to entities
...ode ends up looking like this:
var items = from c in contacts
select new ListItem
{
Value = SqlFunctions.StringConvert((double)c.ContactId).Trim(),
Text = c.Name
};
...
How to pattern match using regular expression in Scala?
... Some(p.Jo.StartsWith(fn)),
Some(p.`.*(\\w)$`.Regexp(lastChar))) =>
println(s"Match! $fn ...$lastChar")
case _ => println("nope")
}
}
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