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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 ...
jQuery: checking if the value of a field is null (empty)
... be null, it's always a string value. this isn't entirely true. I've got a select containing no options. When I perform .val() on this it returns null. Jquery 1.7.2
– Liam
Jan 14 '13 at 11:07
...
What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]
...: String s = GlobalStringObjectCache.get("hello");
– Charles Goodwin
May 30 '16 at 12:07
7
Copy-p...
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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...
String vs. StringBuilder
... .NET are immutable). It works by keeping an internal buffer, an array of char. Calling Append() or AppendLine() adds the string to the empty space at the end of the char array; if the array is too small, it creates a new, larger array, and copies the buffer there. So in the example above, String...
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)" />
<...
Binding a WPF ComboBox to a custom list
I have a ComboBox that doesn't seem to update the SelectedItem/SelectedValue.
4 Answers
...
Python: How to create a unique file name?
... answered Jun 2 '10 at 21:13
Richard BarrellRichard Barrell
4,01122 gold badges1919 silver badges1616 bronze badges
...
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...
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:
...