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How do I negate a condition in PowerShell?
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Perl has a more logical, in the Vulcan sense, idiom, called Unless, which is written as a function. Being half Vulcan, I prefer it, and have implemented it in both C#, as a function, and in C and C++, as a macro.
– David A. Gray
May 30 '18...
Fastest way to implode an associative array with keys
...tes a URL-encoded query string from the associative (or indexed) array provided.
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How do you use variables in a simple PostgreSQL script?
... WHERE Name = v_List;
-- ...
END $$;
Also you can get the last insert id:
DO $$
DECLARE lastid bigint;
BEGIN
INSERT INTO test (name) VALUES ('Test Name')
RETURNING id INTO lastid;
SELECT * FROM test WHERE id = lastid;
END $$;
...
Foreign key from one app into another in Django
...example, if the Manufacturer model above is defined in another application called production, you'd need to use:
class Car(models.Model):
manufacturer = models.ForeignKey('production.Manufacturer')
Have you tried putting it into quotes?
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What is the purpose of the vshost.exe file?
...ment).
The purpose of it is mostly to make debugging launch quicker - basically there's already a process with the framework running, just ready to load your application as soon as you want it to.
See this MSDN article and this blog post for more information.
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Scala equivalent of Java java.lang.Class Object
...like the erasure of the static type of the expression on which getClass is called
It would let me do something like the following where I want to introspect on a class but shouldn't need a class instance.
I also want to limit the types of classes I want to introspect on, so I use Class[_ <: Foo]....
In Clojure, when should I use a vector over a list, and the other way around?
..."Generating Code" = "Inside a Macro" (because most of the code is function calls, thus lists) ; "generating back to front" = "building a sequence by prepending".
– omiel
Apr 4 '14 at 5:14
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Customizing the template within a Directive
...gt;' +
'<label class="control-label" for="' + attrs.formId + '">' + attrs.label + '</label>' +
'<div class="controls">' +
'<input type="' + type + '" class="input-xlarge" id="' + attrs.formId + '" name="' + attrs.formId + '...
Select rows which are not present in other table
...pty in Postgres
FROM ip_location
WHERE ip = l.ip
);
Also consider:
What is easier to read in EXISTS subqueries?
LEFT JOIN / IS NULL
Sometimes this is fastest. Often shortest. Often results in the same query plan as NOT EXISTS.
SELECT l.ip
FROM login_log l
LEFT JOIN ip_locat...
What does iterator->second mean?
...ough two members: first and second. So if you have a std::pair<X, Y> called p, p.first is an X object and p.second is a Y object.
So now you know that dereferencing a std::map iterator gives you a std::pair, you can then access its elements with first and second. For example, (*it).first will...