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Should arrays be used in C++?
...:array<T> allocates on the stacks and basically has no overhead on a raw array.
– 111111
May 23 '12 at 10:46
5
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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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Smart pointers: who owns the object? [closed]
...on of objects are predictable (RAII is your friend, again).
In this model, raw pointers are freely circulating and mostly not dangerous (but if the developer is smart enough, he/she will use references instead whenever possible).
raw pointers
std::auto_ptr
boost::scoped_ptr
Smart Pointed C++ Model...
Adb Devices can't find my phone [closed]
...
I have a ZTE Crescent phone (Orange San Francisco II).
When I connect the phone to the USB a disk shows up in OS X named 'ZTE_USB_Driver'.
Running adb devices displays no connected devices. But after I eject the 'ZTE_USB_Driver' disk from OS X, and run...
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'...
What is the difference between sed and awk? [closed]
...the past 10 years might reveal that people who tend to buy apples also buy oranges or something similar.
– Steam
Aug 20 '13 at 19:56
1
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Apply formula to the entire column
...t's take this as an example:
String array in column "A": {apple, banana, orange, ..., avocado}
You want to substitute the char of "a" to "x" to have: {xpple, bxnxnx,
orxnge, ..., xvocado}
To apply this formula on the entire column (array) in a clean an elegant way, you can do:
=ARRAYFORMULA(SUB...
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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Why can't I use background image and color together?
...
display: inline-block;
}
<div class="box" style="background-color:orange"></div>
<div class="box" style="background-color:green"></div>
<div class="box" style="background-color:blue"></div>
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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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