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Storyboard warning: prototype table cells must have reuse identifiers
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happned to me to. close xcode - open it, and then change the identifier
– Idan Magled
Mar 16 '14 at 20:05
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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_destro...
How to change navbar collapse threshold using Twitter bootstrap-responsive?
...ect, implemented with bootstrap-sass. I'm loading both the bootstrap.css and the bootstrap-responsive.css files, as well as the bootstrap-collapse.js Javascript.
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How can I use “sizeof” in a preprocessor macro?
... ((void)sizeof(... it errors with expected identifier or '(' before 'void' and expected ')' before 'sizeof'. But in principle size_t x = (sizeof(... instead does work as intended. You have to "use" the result, somehow. To allow for this to be called multiple times either inside a function or at gl...
Passing A List Of Objects Into An MVC Controller Method Using jQuery Ajax
...et; set; }
}
There are two things I learned from this:
The contentType and dataType settings are absolutely necessary in the ajax() function. It won't work if they are missing. I found this out after much trial and error.
To pass in an array of objects to an MVC controller method, simply use th...
android: stretch image in imageview to fit screen
I have an imageview that has its height and width set to fill_parent with a linearlayout that has the same values set. So I suppose this should set my images to fit the screen. But it only fits like 80% (margin top and bottom in landscape mode).
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Where is the list of predefined Maven properties
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mvn help:effective-pom stands as a great tool for discovering properties available. maven.apache.org/plugins/maven-help-plugin/…
– Peter Kahn
Jul 4 '16 at 15:01
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Calling class staticmethod within the class body?
When I attempt to use a static method from within the body of the class, and define the static method using the built-in staticmethod function as a decorator, like this:
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SublimeText encloses lines in white rectangles
It's rather annoying and I can't seem to figure out why.
14 Answers
14
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How to create a MySQL hierarchical recursive query
... (select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19' should be set to the id of the parent you want to select all the descendants of.
This will work also if a parent has m...