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linq query to return distinct field values from a list of objects
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objList.Select(o=>o.typeId).Distinct()
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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 ...
What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...
Using boolean values in C
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Why use int for bool? That's wasteful. Use unsigned char. Or use C's builtin _Bool.
– user12211554
May 19 at 21:30
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How to run an EXE file in PowerShell with parameters with spaces and quotes
...eed to quote parameter/argument pairs that contain spaces and/or quotation chars. When you invoke an EXE file like this with complex command line arguments it is usually very helpful to have a tool that will show you how PowerShell sends the arguments to the EXE file. The PowerShell Community Extens...
XPath - Selecting elements that equal a value
In Xpath, I am wanting to select elements that equal a specific value.
2 Answers
2
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Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...
Is 23,148,855,308,184,500 a magic number, or sheer chance?
...eth Lewis in Owatonna .
The thing is that all of them have the exact same charge: $23,148,855,308,184,500.00. If the problem was the space-padding, then how is it that all of them had the exact same $0x1250 ($46.88) charge? Two of them had purchased cigarettes at gas stations, another two had paid ...
LINQ to SQL Left Outer Join
...table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
s...
Easiest way to copy a table from one database to another?
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CREATE TABLE db1.table1 SELECT * FROM db2.table1
where db1 is the destination and db2 is the source
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