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Unresolved specs during Gem::Specification.reset:

...t turned out to be a missing line in the gemspec file: $:.push File.expand_path("../lib", __FILE__) This line is normally at the top of the file (in many of the gems I have recently been working in) and I had commented it out to see why. ...
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ArrayIndexOutOfBoundsException when using the ArrayList's iterator

...oing that right, as far as iterating through the Arraylist goes? No: by calling iterator twice in each iteration, you're getting new iterators all the time. The easiest way to write this loop is using the for-each construct: for (String s : arrayList) if (s.equals(value)) // ... As...
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How to do this in Laravel, subquery where in

...t('product_id'); //don't need ->get() or ->first() and then we put all together: Products::whereIn('id', $productCategory) ->where('active', 1) ->select('id', 'name', 'img', 'safe_name', 'sku', 'productstatusid') ->get();//runs all queries at once Th...
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Nullable types and the ternary operator: why is `? 10 : null` forbidden? [duplicate]

... The compiler first tries to evaluate the right-hand expression: GetBoolValue() ? 10 : null The 10 is an int literal (not int?) and null is, well, null. There's no implicit conversion between those two hence the error message. If you change the right-hand expression to one o...
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Viewing my IIS hosted site on other machines on my network

... As others said your Firewall needs to be configured to accept incoming calls on TCP Port 80. in win 7+ (easy wizardry way) go to windows firewall with advance security Inbound Rules -> Action -> New Rule select Predefined radio button and t...
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Django filter versus get for single object?

... get() is provided specifically for this case. Use it. Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're vio...
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When should I use a composite index?

...olumn_A ) But it will not (at least not directly, maybe it can help partially if there are no better indices) help for queries that need index( column_A, column_C ) Notice how column_B is missing. In your original example, a composite index for two dimensions will mostly benefit queries that q...
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Try-catch speeding up my code?

...eration on the loads and stores of the locals. For some reason unclear to all of us, the problematic code generation path is avoided when the JITter knows that the block is in a try-protected region. This is pretty weird. We'll follow up with the JITter team and see whether we can get a bug enter...
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Mechanisms for tracking DB schema changes [closed]

...ed code to a production server) but we're still doing database updates manually. I would like to find or create a solution that allows us to work efficiently across servers with different environments while continuing to use Subversion as a backend through which code and DB updates are pushed aroun...
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Is it possible to insert multiple rows at a time in an SQLite database?

...blename' SELECT 'data1' AS 'column1', 'data2' AS 'column2' UNION ALL SELECT 'data1', 'data2' UNION ALL SELECT 'data1', 'data2' UNION ALL SELECT 'data1', 'data2' a note on performance I originally used this technique to efficiently load large datasets from Ruby on Rails. However, as Jaime...