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What is the difference between the | and || or operators?
...lways used || (two pipes) in OR expressions, both in C# and PHP. Occasionally I see a single pipe used: | . What is the difference between those two usages? Are there any caveats when using one over the other or are they interchangeable?
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How to find list intersection?
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If order is not important and you don't need to worry about duplicates then you can use set intersection:
>>> a = [1,2,3,4,5]
>>> b = [1,3,5,6]
>>> list(set(a) & set(b))
[1, 3, 5]
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Solving “Who owns the Zebra” programmatically?
... It basically allows concluding of facts from statements made using First Order Logic. FOL is basically a more advanced form of propositional logic. If you decide you don't want to use Prolog, you could use a similar system of your own creation using a technique such as modus ponens to perform th...
LAST_INSERT_ID() MySQL
...tely following the insert:
$result = $conn->query("SELECT * FROM corex ORDER BY id DESC LIMIT 1");
while ($row = $result->fetch_assoc()) {
$id = $row['id'];
}
This retrieves the last id from the database.
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LaTeX package for syntax highlighting of code in various languages
...The minted package supports colors, unicode and looks awesome. However, in order to use it, you need to have python 2.6 and pygments. In Ubuntu, you can check your python version in the terminal with
python --version
and you can install pygments with
sudo apt-get install python-pygments
Then, ...
Structure padding and packing
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+allyourcode The standard guarantees that the order of the members will be preserved and that the first member will start at 0 offset.
– martinkunev
Dec 8 '17 at 14:32
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Can't install RMagick 2.13.1. Can't find MagickWand.h.
...I am wrong, but this your first time installing anything ImageMagick ? In order for rmagick gem to function you need ImageMagick developer libraries, and all of their associated dependencies. So unfortunately, yes you do need all of those packages. On the plus side, your computer will have world ...
LINQ to SQL Left Outer Join
..., for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
select new {
CustomerID = c.CustomerID, ContactName = c.ContactName,
OrderI...
Is it possible to preview stash contents in git?
...shows the last tone, 1 the second last one.. etc. git stash list will show all the available.
– brita_
Jul 18 '14 at 21:13
7
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The relationship could not be changed because one or more of the foreign-key properties is non-nulla
...oesn't make sense to have comments for a post that doesn't exist. Same for orders and order items.
In aggregation, the child object can exist irrespective of its parent. If the parent is destroyed, the child object can still exist, as it may be added to a different parent later. e.g.: the relations...