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generate model using user:references vs user_id:integer
..._id: integer, created_at: datetime, updated_at: datetime)
The second command adds a belongs_to :user relationship in your Micropost model whereas the first does not. When this relationship is specified, ActiveRecord will assume that the foreign key is kept in the user_id column and it will use a ...
Cast an instance of a class to a @protocol in Objective-C
... edited Mar 21 '17 at 21:08
Alexander Abakumov
9,59199 gold badges6363 silver badges9999 bronze badges
answered Nov 26 '10 at 1:47
...
How to force use of overflow menu on devices with menu button
...tually prevented by design. According to the Compatibility Section of the Android Design Guide,
"...the action overflow is available from the menu hardware key. The resulting actions popup... is displayed at the bottom of the screen."
You'll note in the screenshots, phones with a physical menu b...
Why can't Python parse this JSON data?
...ata["maps"][0]["id"]
data["masks"]["id"]
data["om_points"]
Try those out and see if it starts to make sense.
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How does the compilation/linking process work?
... is usually just declarations), doing replacement of macros (#define), and selecting different portions of text depending of #if, #ifdef and #ifndef directives.
The preprocessor works on a stream of preprocessing tokens. Macro substitution is defined as replacing tokens with other tokens (the opera...
On a CSS hover event, can I change another div's styling? [duplicate]
...e adjacent sibling combinator (+).
If there are other elements between #a and #b, you can use this: http://jsfiddle.net/u7tYE/1/
#a:hover ~ #b {
background: #ccc
}
<div id="a">Div A</div>
<div>random other elements</div>
<div>random other elements</div>
<...
How to obtain a Thread id in Python?
I have a multi-threading Python program, and a utility function, writeLog(message) , that writes out a timestamp followed by the message. Unfortunately, the resultant log file gives no indication of which thread is generating which message.
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Convert a series of parent-child relationships into a hierarchical tree?
...sic recursive function to parse the child/parent pairs to a tree structure and another recursive function to print it out. Only one function would suffice but here's two for clarity (a combined function can be found at the end of this answer).
First initialize the array of child/parent pairs:
$tre...
What is href=“#” and why is it used?
...lt;div id="some-id">.
href="//site.com/#some-id" would go to site.com and scroll to the id on that page.
Scroll to Top:
href="#" doesn't specify an id name, but does have a corresponding location - the top of the page. Clicking an anchor with href="#" will move the scroll position to the top....
How can I get Docker Linux container information from within the container itself?
...
Aaaaand Docker 1.12: cat /proc/1/cgroup | grep 'docker/' | tail -1 | sed 's/^.*\///' | cut -c 1-12
– smets.kevin
Jul 27 '16 at 21:05
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