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SQL Server 2005 How Create a Unique Constraint?
... you want to do it from a Database Diagram:
right-click on the table and select 'Indexes/Keys'
click the Add button to add a new index
enter the necessary info in the Properties on the right hand side:
the columns you want (click the ellipsis button to select)
set Is Unique to Yes
give it an app...
How do you configure Django for simple development and deployment?
..., Python, Django, etc. As part of the installation process we allow you to select which database you want to use (MySQL, SQLite, PostgreSQL). We use the installers extensively when automating deployments internally (they can be run in unattended mode).
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Why are joins bad when considering scalability?
...en so can you.
There are many reasons not to denomalize. First, speed of select queries is not the only or even main concern with databases. Integrity of the data is the first concern. If you denormalize then you have to put into place techniques to keep the data denormalized as the parent data ch...
Maven: Failed to read artifact descriptor
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Had the same issue with IntelliJ IDEA and following worked.
Go to File
Select Settings
Select Build, Execution, Deployments
Select Build Tools from drop down
Select Maven from drop down
Tick the Always update snapshots check box
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What's the difference between using INDEX vs KEY in MySQL?
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Here is a nice description about the "difference":
"MySQL requires every Key also be indexed, that's an implementation
detail specific to MySQL to improve performance."
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rbenv not changing ruby version
...ving with YUM in Centos 7, only after that I could see the correct version selected in rbenv
– Joe Walker
Jun 16 '16 at 22:26
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Table is marked as crashed and should be repaired
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Run this from your server's command line:
mysqlcheck --repair --all-databases
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What is the best way to paginate results in SQL Server
... sake of this example, let's assume that the query you're dealing with is
SELECT * FROM Orders WHERE OrderDate >= '1980-01-01' ORDER BY OrderDate
In this case, you would determine the total number of results using:
SELECT COUNT(*) FROM Orders WHERE OrderDate >= '1980-01-01'
...which may ...
How can I get the SQL of a PreparedStatement?
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This also depends on the implementation. In MySQL -- at least the version I was using a few years ago -- the JDBC driver actually built a conventional SQL query from the template and bind variables. I guess that version of MySQL didn't support prepared statements nativ...
Why is MySQL's default collation latin1_swedish_ci?
...rs? they changed this into a sane default, like utf8_general_ci. Good job, MySQL !
– Michael Trouw
Sep 24 '15 at 10:17
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