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Do fragments really need an empty constructor?

... Yes they do. You shouldn't really be overriding the constructor anyway. You should have a newInstance() static method defined and pass any parameters via arguments (bundle) For example: public static final MyFragment newInstance(int title, String messa...
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Getting exact error type in from DbValidationException

...ity.Validation.DbEntityValidationResult} which gives me no information at all about what field it was unable to initialize. Is there a way to get more info about this error? ...
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Difference between database and schema

... A database is the main container, it contains the data and log files, and all the schemas within it. You always back up a database, it is a discrete unit on its own. Schemas are like folders within a database, and are mainly used to group logical objects together, which leads to ease of setting pe...
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How to get progress from XMLHttpRequest

... { if (req.readyState == 4) { //run any callback here } }; req.send(); } share | improve this answer | follow ...
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PostgreSQL: Show tables in PostgreSQL

...terface, First, choose your database \c database_name Then, this shows all tables in the current schema: \dt Programmatically (or from the psql interface too, of course): SELECT * FROM pg_catalog.pg_tables; The system tables live in the pg_catalog database. ...
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Select DISTINCT individual columns in django?

...g note in the docs about using distinct(). The above example will work but all combinations of distinct() and values() may not. PS: it is a good idea to use lower case names for fields in a model. In your case this would mean rewriting your model as shown below: class ProductOrder(models.Model): ...
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Difference between shadowing and overriding in C#?

...dow public override int Bar() {return 1;} //override } then when you call this: A clA = new A(); B clB = new B(); Console.WriteLine(clA.Foo()); // output 5 Console.WriteLine(clA.Bar()); // output 5 Console.WriteLine(clB.Foo()); // output 1 Console.WriteLine(clB.Bar()); // output 1 //now let'...
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Make .gitignore ignore everything except a few files

...han the root dir won't be found anyway. I'm using this now (with *.pl) and all *.pl files are being ignored even though there are many in the subdirectories below the .gitignore file – PandaWood Nov 6 '11 at 1:44 ...
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Declaring Multiple Variables in JavaScript

...ou're writing code that you expect to minify or pack later, the second way allows compressors (like the YUI Compressor) to give you a more minified version. If size is a consideration, then I would suggest following as many of JSLint's suggestions as possible. – Lane ...
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How to test if parameters exist in rails

...re asking about existence. You might need to differentiate: Not there at all. There but nil. There but false. There but an empty string. as well. Hard to say without more details of your precise situation. share ...