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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versi...
Why does NULL = NULL evaluate to false in SQL server
... in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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How to get the type of T from a member of a generic class or method?
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If I understand correctly, your list has the same type parameter as the container class itself. If this is the case, then:
Type typeParameterType = typeof(T);
If you are in the lucky situation of having object as a type parameter, see...
Haskell: Lists, Arrays, Vectors, Sequences
I'm learning Haskell and read a couple of articles regarding performance differences of Haskell lists and (insert your language)'s arrays.
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How to render a DateTime in a specific format in ASP.NET MVC 3?
... iterating an IEnumerable<T>. Creating a template is simple enough, and can provide a lot of flexibility too. Create a folder in your views folder for the current controller (or shared views folder) called DisplayTemplates. Inside that folder, add a partial view with the model type you want...
What is the difference between “AS” and “IS” in an Oracle stored procedure?
I see Oracle procedures sometimes written with "AS", and sometimes with "IS" keyword.
6 Answers
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Restore LogCat window within Android Studio
I have recently started to use Android Studio v0.1.1, And i can't seem to find LogCat... Is it gone? Or if not, how can I enable it?
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How to exit a 'git status' list in a terminal?
I'm new to Git and the terminal. How can I exit a listing mode generated by the git status command?
14 Answers
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Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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What are 'get' and 'set' in Swift?
I'm learning Swift and I'm reading The Swift Programming Language from Apple, I have no Objective C background (only PHP, JS, and other but no Obj C)
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