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Primary key or Unique index?
..., if the value is used for nothing? It's make-work in order to stop Access from asking for a PK. Make a PK if you need to identify the record in a child, otherwise it's a waste.
– Mark Brady
Feb 16 '09 at 20:57
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Ruby class instance variable vs. class variable
...lass variables, you have the convenience of not having to write self.class from an instance object, and (when desirable) you also get automatic sharing throughout the class hierarchy.
Merging these together into a single example that also covers instance variables on instances:
class Parent
@@...
How does the Meteor JavaScript framework work? [closed]
...eb applications work like this:
You have scripts on server which take data from database and add that dynamically to web-pages and the user-submitted data gets added to databases through some other scrips.
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How to enable/disable bluetooth programmatically in android
...is call returns true, then the adapter
state will immediately transition from STATE_OFF to STATE_TURNING_ON,
and some time later transition to either STATE_OFF or STATE_ON. If
this call returns false then there was an immediate problem that will
prevent the adapter from being turned on - suc...
return, return None, and no return at all?
...re. return None is never used if there are no other possible return values from the function.
In the following example, we return person's mother if the person given is a human. If it's not a human, we return None since the person doesn't have a mother (let's suppose it's not an animal or something...
How do I prevent angular-ui modal from closing?
... As question stated, Tell me a logic, which will prevent modal from closing ?
– Rahul Prasad
Apr 16 '16 at 12:39
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How to handle AccessViolationException
I am using a COM object (MODI) from within my .net application. The method I am calling throws a System.AccessViolationException, which is intercepted by Visual Studio. The odd thing is that I have wrapped my call in a try catch, which has handlers for AccessViolationException, COMException and ev...
Capturing TAB key in text box [closed]
...y to prevent the default action, moving to the next item in the tab order, from occurring.
In Firefox you can call the preventDefault() method on the event object passed to your event handler. In IE, you have to return false from the event handle. The JQuery library provides a preventDefault method...
How do I attach events to dynamic HTML elements with jQuery? [duplicate]
...ater jQuery releases. The .live() method is deprecated as of jQuery 1.7.
From http://api.jquery.com/live/
As of jQuery 1.7, the .live() method is deprecated. Use .on() to attach event handlers. Users of older versions of jQuery should use .delegate() in preference to .live().
For jQuery 1.7...
How can I fix WebStorm warning “Unresolved function or method” for “require” (Firefox Add-on SDK)
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Enable the NodeJS plugin if 'Node.js Globals' is missing from the library list.
– 0x539
Aug 1 '17 at 17:00
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