大约有 44,000 项符合查询结果(耗时:0.0554秒) [XML]
Get top 1 row of each group
...s will arbitrarily pick one. To get both entries for a day, use DENSE_RANK instead
As for normalised or not, it depends if you want to:
maintain status in 2 places
preserve status history
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As it stands, you preserve status history. If you want latest status in the parent table too (which is ...
How do you delete an ActiveRecord object?
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It's destroy and destroy_all methods, like
user.destroy
User.find(15).destroy
User.destroy(15)
User.where(age: 20).destroy_all
User.destroy_all(age: 20)
Alternatively you can use delete and delete_all which won't enforce :before_destroy and :after_destroy callbacks or any dependent as...
MySQL Select all columns from one table and some from another table
... all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Encoding Javascript Object to Json string
I want to encode a Javascript object into a JSON string and I am having considerable difficulties.
2 Answers
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Where'd padding go, when setting background Drawable?
...ve this issue on my EditText and Button views, where I have a nice padding for them to space away from the text, but when I change the background with setBackgroundDrawable or setBackgroundResource that padding is lost forever.
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Team city unmet requirement: MSBuildTools12.0_x86_Path exists
I have a TeamCity install on x32 Server2008 windows machine. I've run the .net 4.5 web install. I've also copied over the files from my x64 machine based on this article so that I didn't need to install vs2012 (though, I did have the change the path to remove x86 on the 32bit machine):
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Add new field to every document in a MongoDB collection
How can I add a new field to every document in an existent collection?
5 Answers
5
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android webview geolocation
I have to retrieve a user's location in a WebView . I do this with the following Javascript:
6 Answers
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How to run two jQuery animations simultaneously?
...elements simultaneously? I need the opposite of this question Jquery queueing animations .
7 Answers
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SQLAlchemy: how to filter date field?
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In fact, your query is right except for the typo: your filter is excluding all records: you should change the <= for >= and vice versa:
qry = DBSession.query(User).filter(
and_(User.birthday <= '1988-01-17',...