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Primary key or Unique index?
...value appears nowhere, 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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Create a File object in memory from a string in Java
...nt to create/write a new File (I don't have write access to filesystem) in order to pass my string data to the function. I should add that the String data don't exist in a file (so I cannot read my data from a file).
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Multiline string literal in C#
...literal I find is that it can make your code look a bit "weird" because in order to not get spaces in the string itself, it has to be completely left aligned:
var someString = @"The
quick
brown
fox...";
Yuck.
So the solution I like to use, which keeps everything nicely aligned with the res...
How to return a result from a VBA function
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How does Activity.finish() work in Android?
...events are getting posted.
This thread can execute all these events in the order of insertion.
If you are calling finish() in one of the life cycle callbacks like onCreate()...a "finish" message will get added to this queue but the thread is not free to pick & execute "finish" action
until curr...
Regular Expression for alphanumeric and underscores
..., which the range based regexes won't do since they rely on the underlying ordering of the ASCII characters which may be different from other character sets and will therefore exclude some non-ASCII characters (letters such as œ) which you might want to capture.
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Is there a simple, elegant way to define singletons? [duplicate]
...the imports. For example, Python logging is a module level interface. In order to ensure you fully clean up after logging you must call logging.shutdown(). This means you must import logging into the module which calls shutdown. If it was a singleton pattern it is possible to call shutdown on th...
How to make an AJAX call without jQuery?
...our code execution will go on, while your file loads in the background. In order to use the content of the file in your script you need a mechanism that tells your script when the file finished loading or failed loading. That's where promises come in handy. There are other ways to solve this problem...
Difference between Document-based and Key/Value-based databases?
...plex queries, your application will have to create and maintain indexes in order to access the desired data.
Document databases support queries by key and map-reduce functions as well, but also allow you to do basic queries by value, such as "Give me all users with more than 10 posts". Document dat...
Xcode 4, Core Data Model Version - Set Current Version
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A little off topic, but if you've reached this question in order to know how to create a first new version of your model (like i did) :
click on the xcdatamodel file >> Menu "Editor" >> Add Model version
This will initiate the versionning of the model.
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