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MongoDB - Update objects in a document's array (nested updating)
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For question #1, let's break it into two parts. First, increment any document that has "items.item_name" equal to "my_item_two". For this you'll have to use the positional "$" operator. Something like:
db.bar.update( {user_id : 123456 , "items.item_name" : "my_item_two" } ,
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postgresql COUNT(DISTINCT …) very slow
...the replies (by Jeff Janes) says that COUNT(DISTINCT()) sorts the table to do its work instead of using hash.
– Ankur
Dec 9 '14 at 10:58
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How can I do SELECT UNIQUE with LINQ?
...passed into function} => {object used to sort}. Since we have already done the Select, the only thing in the collection being sorted is the names.
– James Curran
Aug 20 '10 at 11:35
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In Gradle, how do I declare common dependencies in a single place?
...Management to define what version of the lib it should take. How would you do the same with Gradle?
– Stanislav Bashkyrtsev
Mar 5 '12 at 13:04
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What Makes a Good Unit Test? [closed]
...f test execution. Ensure 'clean slate' before each test by using setup/teardown appropriately
Professional: In the long run you'll have as much test code as production (if not more), therefore follow the same standard of good-design for your test code. Well factored methods-classes with intention-r...
Android Fragments. Retaining an AsyncTask during screen rotation or configuration change
...mmended replacement for Activity.onRetainnonConfigurationInstance() in the docs.
If for some reason you really don't want to use a retained fragment, there are other approaches you can take. Note that each fragment has a unique identifier returned by Fragment.getId(). You can also find out if a f...
Haskell Type vs Data Constructor
...uble understanding type constructors and data constructors. For example, I don't really understand the difference between this:
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AngularJS Directive Restrict A vs E
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According to the documentation:
When should I use an attribute versus an element? Use an element when
you are creating a component that is in control of the template. The
common case for this is when you are creating a Domain-Specific...
How do I access the command history from IDLE?
On bash or Window's Command Prompt, we can press the up arrow on keyboard to get the last command, and edit it, and press ENTER again to see the result.
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Big O, how do you calculate/approximate it?
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I'll do my best to explain it here on simple terms, but be warned that this topic takes my students a couple of months to finally grasp. You can find more information on the Chapter 2 of the Data Structures and Algorithms in Java ...