大约有 522 项符合查询结果（耗时：0.0204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...
代码块超过1.2w编译apk报错问题 - App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
报错信息：
3月 04, 2025 9:50:11 上午 com.google.appengine.tools.development.ApiProxyLocalImpl log
严重: javax.servlet.ServletContext log: Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract long com.google.appinv...
Why does the month argument range from 0 to 11 in JavaScript's Date constructor?
...dont deprecate this it will still happen - feel free to coment in the year 2025 and on ;-)
– Mauricio Gracia Gutierrez
Oct 8 '19 at 14:39
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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') ...