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Does MySQL ignore null values on unique constraints?
... '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
...
Pass An Instantiated System.Type as a Type Parameter for a Generic Class
...amic is still rooted to a strongly typed language the run time binder will select the appropriate Markdown method. If there is no exact type matches, it will look for an object parameter method and if neither match a runtime binder exception will be raised alerting that no method matches.
The obvio...
Git Remote: Error: fatal: protocol error: bad line length character: Unab
...o 2.19.0
Solution:
Tools > Settings > Git Extensions > SSH
Select [OpenSSH] instead of [PuTTY]
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Storyboard - refer to ViewController in AppDelegate
...
If you use XCode 5 you should do it in a different way.
Select your UIViewController in UIStoryboard
Go to the Identity Inspector on the right top pane
Check the Use Storyboard ID checkbox
Write a unique id to the Storyboard ID field
Then write your code.
// Override point for ...
renderpartial with null model gets passed the wrong type
...s to be what it is doing. You will have to cast it to an object for it to select the correct constructor.
– Joel McBeth
Jul 27 '11 at 15:15
1
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How does Spring Data JPA differ from Hibernate for large projects?
...ryCustom {
List<MyObject> findByName(String name);
@Query("select * from my_object where name = ?0 or middle_name = ?0")
List<MyObject> findByFirstNameOrMiddleName(String name);
}
MyObjectRepositoryCustom - repository methods that are more complex and cannot be handled wi...
Storing JSON in database vs. having a new column for each key
..._food pizza
.................
and query via something like this:
select meta_val from `table` where meta_key = 'name' and uid = 1 order by meta_id desc
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nginx - nginx: [emerg] bind() to [::]:80 failed (98: Address already in use)
...at I would future readers of your question to do. That's why I suggest you select @Nathan's answer as the correct answer.
– Oliver
Mar 18 '13 at 11:23
4
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Simulator or Emulator? What is the difference?
...e than it is.
This comparison of both terms will contradict the currently selected answer (from Toybuilder) which puts the difference on the internal model, while my suggestion is that the difference is whether the fake can or cannot be used to perform the actual function in the actual world (to so...
Difference between Rebuild and Clean + Build in Visual Studio
..., right click on the desired project name in the Solution Explorer tab and select Set as StartUp project. The project name now appears in bold. Since the homework solutions typically have only one project, Build or Rebuild Solution is effectively the same as Build or Rebuild .
Compile just compiles...