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SQL Server - When to use Clustered vs non-Clustered Index?
I know primary differences between clustered and non clustered indexes and have an understanding of how they actually work. I understand how clustered and non-clustered indexes improve read performance. But one thing I am not sure is that what would be the reasons where I would choose one over the o...
Entity Framework code first unique column
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In Entity Framework 6.1+ you can use this attribute on your model:
[Index(IsUnique=true)]
You can find it in this namespace:
using System.ComponentModel.DataAnnotations.Schema;
If your model field is a string, make sure it is not set to nvarchar(MAX) in SQL Server or you will see this er...
Using wget to recursively fetch a directory with arbitrary files in it
...-recursive, of course), otherwise it will follow the link in the directory index on my site to the parent directory. So the command would look like this:
wget --recursive --no-parent http://example.com/configs/.vim/
To avoid downloading the auto-generated index.html files, use the -R/--reject opt...
Auto increment in phpmyadmin
... Had a similar issue and this fixed my problem
– Callat
Sep 4 '17 at 15:44
1
wow, so simple. w...
How to mark-up phone numbers?
I want to mark up a phone number as callable link in an HTML document. I have read the microformats approach , and I know, that the tel: scheme would be standard, but is quite literally nowhere implemented.
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How do I create a unique constraint that also allows nulls?
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SQL Server 2008 +
You can create a unique index that accept multiple NULLs with a WHERE clause. See the answer below.
Prior to SQL Server 2008
You cannot create a UNIQUE constraint and allow NULLs. You need set a default value of NEWID().
Update the existing valu...
conditional unique constraint
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Behold, the filtered index. From the documentation (emphasis mine):
A filtered index is an optimized nonclustered index especially suited to cover queries that select from a well-defined subset of data. It uses a filter predicate to index a p...
Xcode stuck on Indexing
...g for 2 months stopped working for no reason because Xcode got stucked on "Indexing". I can't Build the project anymore. If I try to build, Xcode freezes and I have to force quit. This happens only with this project.
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How to replace an item in an array with Javascript?
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var index = items.indexOf(3452);
if (index !== -1) {
items[index] = 1010;
}
Also it is recommend you not use the constructor method to initialize your arrays. Instead, use the literal syntax:
var items = [523, 3452, 334, ...
Convert form data to JavaScript object with jQuery
...now this is a few months old, but since when did do arrays use non-numeric indexes? No one should name an input foo[bar] and hope to treat it as an array. Are you confusing arrays and hashes? Yes, [] is commonly understood to be an accessor but not just for arrays. Also saying it's valid HTML but no...