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SQL how to increase or decrease one for a int column in one command
I have an Orders table which has a Quantity column. During check in or check out, we need to update that Quantity column by one. Is there a way to do this in one action or we have to get the existing value and then add or minus one on top of it?
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INNER JOIN vs LEFT JOIN performance in SQL Server
...clustered index scans with a seek - meaning that this will literally be an order of magnitude faster with a large number of rows.
So the conclusion is more or less what I mentioned several paragraphs above; this is almost certainly an indexing or index coverage problem, possibly combined with one o...
Check if two lists are equal [duplicate]
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var a = ints1.SequenceEqual(ints2);
Or if you don't care about elements order use Enumerable.All method:
var a = ints1.All(ints2.Contains);
The second version also requires another check for Count because it would return true even if ints2 contains more elements than ints1. So the more correct...
nginx missing sites-available directory
... virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
3 Answers
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How to list all users in a Linux group?
...no good, portable way to do this that I know of. If you attempt to parse /etc/group, as others are suggesting, you will miss users who have that group as their primary group and anyone who has been added to that group via a mechanism other than UNIX flat files (i.e. LDAP, NIS, pam-pgsql, etc.).
If...
What's the difference between IQueryable and IEnumerable
... code), which an IQueryProvider must explore/interpret/compile/whatever in order to generate results.
Having a query expression gives two advantages.
The first advantage is optimization. Because modifiers like 'Where' are included in the query expression, the IQueryProvider can apply otherwise imp...
What does yield mean in PHP?
...d of returning once, a generator can yield as many times as it needs to in order to provide the values to be iterated over.
From this place: generators = generators, other functions (just a simple functions) = functions.
So, they are useful when:
you need to do things simple (or simple things);
ge...
How can I find the version of the Fedora I use?
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cat /etc/issue
Or cat /etc/fedora-release as suggested by @Bruce ONeel
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What's the difference between IComparable & IEquatable interfaces?
...atable tests whether two objects are equal.
IComparable imposes a total ordering on the objects being compared.
For example, IEquatable would tell you that 5 is not equal to 7. IComparable would tell you that 5 comes before 7.
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Can I use my existing git repo with openshift?
...lias here:
git remote add openshift -f <openshift-git-repo-url>
In order to then be able to push the code from your local git repo to openshift you first have to merge your openshift repo with your local bitbucket clone. You do that by issuing locally:
git merge openshift/master -s recursiv...