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Get records with max value for each group of grouped SQL results
How do you get the rows that contain the max value for each grouped set?
17 Answers
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PersistentObjectException: detached entity passed to persist thrown by JPA and Hibernate
I have a JPA-persisted object model that contains a many-to-one relationship: an Account has many Transactions . A Transaction has one Account .
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How can I erase all inline styles with javascript and leave only the styles specified in the css sty
If I have the following in my html:
7 Answers
7
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HTML form readonly SELECT tag/input
According to HTML specs, the select tag in HTML doesn't have a readonly attribute, only a disabled attribute. So if you want to keep the user from changing the dropdown, you have to use disabled .
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How can I change an element's class with JavaScript?
How can I change a class of an HTML element in response to an onclick event using JavaScript?
32 Answers
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How do I see active SQL Server connections?
I am using SQL Server 2008 Enterprise. I want to see any active SQL Server connections, and the related information of all the connections, like from which IP address, connect to which database or something.
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Facebook App: localhost no longer works as app domain
I've been writing a game for Facebook using Rails and jQuery. Since I started using the Facebook Javascript SDK, using localhost as an app domain seemed to work just fine. I was able to test my game both locally and on Heroku.
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method of iterating over sqlalchemy model's defined columns?
I've been trying to figure out how to iterate over the list of columns defined in a SQLAlchemy model. I want it for writing some serialization and copy methods to a couple of models. I can't just iterate over the obj.__dict__ since it contains a lot of SA specific items.
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With MySQL, how can I generate a column containing the record index in a table?
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You may want to try the following:
SELECT l.position,
l.username,
l.score,
@curRow := @curRow + 1 AS row_number
FROM league_girl l
JOIN (SELECT @curRow := 0) r;
The JOIN (SELECT @curRow := 0) part allows the variable in...
Query EC2 tags from within instance
Amazon recently added the wonderful feature of tagging EC2 instances with key-value pairs to make management of large numbers of VMs a bit easier.
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