大约有 418 项符合查询结果（耗时：0.0222秒） [XML]
Limiting the number of records from mysqldump?
...ault to and advise "id" for PK-columns, since it is redundant to say users.user_id instead of just users.id.
– Andreas Bergström
Nov 23 '17 at 8:50
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how to permit an array with strong parameters
...y
params.require(:question).permit(:question_details, :question_content, :user_id, :accepted_answer_id, :province_id, :city, :category_ids => [])
Works perfectly now!
(IMPORTANT: As @Lenart notes in the comments, the array declarations must be at the end of the attributes list, otherwise you'...
delete_all vs destroy_all?
...l
You can do :
u = User.find_by_name('JohnBoy')
UsageIndex.destroy_all "user_id = #{u.id}"
The result is one query to destroy all the associated records
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What is the meaning of the CascadeType.ALL for a @ManyToOne JPA association
...dresses {
@ManyToOne(cascade = CascadeType.REFRESH) @JoinColumn(name = "user_id")
protected User addressOwner;
}
This way you dont need to worry about using fetch in annotations. But remember when deleting the User you will also delete connected address to user object.
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Does SQLAlchemy have an equivalent of Django's get_or_create?
...s, it is automatically added to the session. E.g. create a book, which has user_id and user as corresponding relationship, then doing book.user=<user object> inside of create_method will add book to the session. This means that create_method must be inside with to benefit from an eventual roll...
How to differ sessions in browser-tabs?
...ur AJAX function check first to make sure localStorage.currently_logged_in_user_id === window.yourAppNameSpace.user_id, and if not, log in first via AJAX.
Another is race conditions: if you can switch windows fast enough to confuse it, you may end up with a relogin1->relogin2->ajax1->ajax2...
What's the difference between belongs_to and has_one?
...s. We can say that a User "has" a Profile because the profiles table has a user_id column. If there was a column called profile_id on the users table, however, we would say that a Profile has a User, and the belongs_to/has_one locations would be swapped.
here is a more detailed explanation.
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sqlalchemy: how to join several tables by one query?
...om"
).all()
One note about that...
query.join(Address, User.id==Address.user_id) # explicit condition
query.join(User.addresses) # specify relationship from left to right
query.join(Address, User.addresses) # same, with explicit target
query.join('addresses') ...
How to convert JSON to CSV format and store in a variable
...,description,link,timestamp,image,embed,language,user,user_image,user_link,user_id,geo,source,favicon,type,domain,id
"Apple iPhone 4S Sale Cancelled in Beijing Amid Chaos (Design You Trust)","Advertise here with BSA Apple cancelled its scheduled sale of iPhone 4S in one of its stores in China’s ca...
Naming of ID columns in database tables
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Kevin, same as you. for example: user_id, role_id for PKey, and role_user_id for FKey. It is good on a large scale project. Because if all ID field are named to "id", it is too confuse. But i think it is personal preference, somebody think only use "id" are ...