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How to force LINQ Sum() to return 0 while source collection is empty

...word && l.Property.PropertyId == PropertyId) .Select(l => l.Amount) .DefaultIfEmpty(0) .Sum(); This way, your query will only select the Amount field. If the collection is empty, it will return one element with the value of 0 and then the sum will ...
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Binding a WPF ComboBox to a custom list

I have a ComboBox that doesn't seem to update the SelectedItem/SelectedValue. 4 Answers ...
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AngularJs: How to check for changes in file input fields?

...er="form-cntlr"> <form> <button ng-click="selectFile()">Upload Your File</button> <input type="file" style="display:none" id="file" name='file' onchange="angular.element(this).scope().fileNameChanged(this)" /> <...
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Preventing an image from being draggable or selectable without using JS

Does anyone know of a way to make an image not draggable and not selectable -- at the same time -- in Firefox, without resorting to Javascript? Seems trivial, but here's the issue: ...
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What's the fastest way to do a bulk insert into Postgres?

...200, 300]), UNNEST(ARRAY['a', 'b', 'c']) ); without VALUES using subselect with additional existance check: INSERT INTO tablename (fieldname1, fieldname2, fieldname3) SELECT * FROM ( SELECT UNNEST(ARRAY[1, 2, 3]), UNNEST(ARRAY[100, 200, 300]), UNNEST(ARRAY['a', 'b...
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Why use the SQL Server 2008 geography data type?

...tance < 500 * 1609.344 orderby distance select f; return q1.FirstOrDefault(); } Then there is a very good reason to use Geography. Explanation of spatial within Entity Framework. Updated with Creating High Performance Spatial Databases As I noted on Noe...
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Laravel Eloquent groupBy() AND also return count of each group

...working for me: $user_info = DB::table('usermetas') ->select('browser', DB::raw('count(*) as total')) ->groupBy('browser') ->get(); share | ...
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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?

...pdated) values(null, null); Query OK, 1 row affected (0.06 sec) mysql> select * from t5; +----+---------------------+---------------------+ | id | stamp_created | stamp_updated | +----+---------------------+---------------------+ | 2 | 2009-04-30 09:44:35 | 2009-04-30 09:44:35 | +...
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What is a Proxy in Doctrine 2?

...protected $lastname; // bunch of setters/getters here } DQL query: SELECT u.id, u.username FROM Entity\User u WHERE u.id = :id As you can see this query doesn't return firstname and lastname properties, therefore you cannot create User object. Creation of incomplete entity could lead to un...
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How to make the first option of selected with jQuery

How do I make the first option of selected with jQuery? 27 Answers 27 ...