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Is it fine to have foreign key as primary key?
...n to this are tables with a one-to-one relationship, where the foreign key and primary key of the linked table are one and the same.
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How can I index a MATLAB array returned by a function without first assigning it to a local variable
...3, 3); % Use the function to index the matrix
However, when all is said and done the temporary local variable solution is much more readable, and definitely what I would suggest.
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Count the number of occurrences of a character in a string in Javascript
...a regular expression literal if you know what you are searching for beforehand, if not you can use the RegExp constructor, and pass in the g flag as an argument.
match returns null with no results thus the || []
The original answer I made in 2009 is below. It creates an array unnecessarily, but us...
What is the difference between Scala's case class and class?
I searched in Google to find the differences between a case class and a class . Everyone mentions that when you want to do pattern matching on the class, use case class. Otherwise use classes and also mentioning some extra perks like equals and hash code overriding. But are these the only reasons...
Why is Dictionary preferred over Hashtable in C#?
... safety with Dictionary<TKey, TValue>, because you can't insert any random object into it, and you don't have to cast the values you take out.
Interestingly, the Dictionary<TKey, TValue> implementation in the .NET Framework is based on the Hashtable, as you can tell from this comment in...
How does data binding work in AngularJS?
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AngularJS remembers the value and compares it to a previous value. This is basic dirty-checking. If there is a change in value, then it fires the change event.
The $apply() method, which is what you call when you are transitioning from a non-AngularJS wo...
Modifying location.hash without page scrolling
We've got a few pages using ajax to load in content and there's a few occasions where we need to deep link into a page. Instead of having a link to "Users" and telling people to click "settings" it's helpful to be able to link people to user.aspx#settings
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Can't find the 'libpq-fe.h header when trying to install pg gem
...nx), 11.10 (Oneiric Ocelot), 12.04 (Precise Pangolin), 14.04 (Trusty Tahr) and 18.04 (Bionic Beaver)):
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/usr/include/postgresql/libpq-fe.h
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So try installing libpq-dev or its equivalent for your OS:
For Ubuntu/Debian systems: sudo apt-get install libpq-dev
On Red Hat Linux (RHEL) systems:...
Script to get the HTTP status code of a list of urls?
...rs will notice that this uses one curl process per URL, which imposes fork and TCP connection penalties. It would be faster if multiple URLs were combined in a single curl, but there isn't space to write out the monsterous repetition of options that curl requires to do this.)
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Best way to get identity of inserted row?
...rns the last identity value generated for any table in the current session and the current scope. Generally what you want to use.
IDENT_CURRENT('tableName') returns the last identity value generated for a specific table in any session and any scope. This lets you specify which table you want the v...