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CROSS JOIN vs INNER JOIN in SQL
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2. CROSS JOIN
Cross join selects the all the rows from the first table and all the rows from second table and shows as Cartesian product ie, with all possibilities
Consider we need to find all the teachers in the school and students irrespective of class teacher...
How to use Git and Dropbox together effectively?
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I think that Git on Dropbox is great. I use it all the time. I have multiple computers (two at home and one at work) on which I use Dropbox as a central bare repository. Since I don’t want to host it on a public service, and I don’t have access to a server that I can ...
Git Pull While Ignoring Local Changes?
...it stash
git pull
git stash pop
I don't think it makes any sense to literally ignore the changes, though - half of pull is merge, and it needs to merge the committed versions of content with the versions it fetched.
share
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Find XOR of all numbers in a given range
You are given a large range [a,b] where 'a' and 'b' can be typically between 1 and 4,000,000,000 inclusive. You have to find out the XOR of all the numbers in the given range.
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Simple explanation of MapReduce?
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Going all the way down to the basics for Map and Reduce.
Map is a function which "transforms" items in some kind of list to another kind of item and put them back in the same kind of list.
suppose I have a list of numbers: [1,2...
Are C++ enums signed or unsigned?
...integral type is used as the underlying type for an enum, except that it shall not be larger than int, unless some value cannot fit into int or an unsigned int.
In short: you cannot rely on an enum being either signed or unsigned.
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SQL exclude a column using SELECT * [except columnA] FROM tableA?
We all know that to select all columns from a table, we can use
41 Answers
41
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Regexp Java for password validation
...ecial character must occur at least once
(?=\S+$) # no whitespace allowed in the entire string
.{8,} # anything, at least eight places though
$ # end-of-string
It's easy to add, modify or remove individual rules, since every rule is an independent "module".
Th...
What is a 'Closure'?
... scope
When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languag...
How can I use Google's Roboto font on a website?
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You don't really need to do any of this.
Go to Google's Web Fonts page
search for Roboto in the search box at the top right
Select the variants of the font you want to use
click 'Select This Font' at the top and choose the weights an...