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How can I create a unique constraint on my column (SQL Server 2008 R2)?
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To create these constraints through the GUI you need the "indexes and keys" dialogue not the check constraints one.
But in your case you just need to run the piece of code you already have. It doesn't need to be entered into the expression dialogue at all.
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boost Composite keys - C/C++ - 清泛网 - 专注C/C++及内核技术
...n two or more fields of a given table The analogous concept in Boost MultiIndex is Composite keys
In relational databases, composite keys depend on two or more fields of a given table. The analogous concept in Boost.MultiIndex is modeled by means of composite_key, as shown in the example:
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git update-index --assume-unchanged returns “fatal unable to mark file”
...ng git ls-files -o. However in my case, I also tried executing git update-index --assume-unchanged against a file that was not listed when executing ls-files -o, and I still received the same error "fatal: Unable to mark file".
I thought that perhaps it was a bug, and downloaded the latest version...
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...
Insert an element at a specific index in a list and return the updated list
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l.insert(index, obj) doesn't actually return anything. It just updates the list.
As ATO said, you can do b = a[:index] + [obj] + a[index:].
However, another way is:
a = [1, 2, 4]
b = a[:]
b.insert(2, 3)
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Find index of last occurrence of a substring in a string
I want to find the position (or index) of the last occurrence of a certain substring in given input string str .
9 Answers...
How to remove multiple indexes from a list at the same time? [duplicate]
...to do this in a loop, there is no built-in operation to remove a number of indexes at once.
Your example is actually a contiguous sequence of indexes, so you can do this:
del my_list[2:6]
which removes the slice starting at 2 and ending just before 6.
It isn't clear from your question whether i...
Angular ng-repeat Error “Duplicates in a repeater are not allowed.”
...w in [1,1,1]">
However, changing the above code slightly to define an index to determine uniqueness as below will get it working again.
// This will work
<div ng-repeat="row in [1,1,1] track by $index">
Official docs are here: https://docs.angularjs.org/error/ngRepeat/dupes
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How to remove element from array in forEach loop?
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}
var review = ['a', 'b', 'c', 'b', 'a'];
review.forEach(function(item, index, object) {
if (item === 'a') {
object.splice(index, 1);
}
});
log(review);
<pre id="out"></pre>
Which works fine for simple case where you do not have 2 of the same values as adjacent array i...
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...