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How to expand folded package chain in Intellij IDEA?
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2 Answers
2
Active
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How do you delete an ActiveRecord object?
... 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_destroy and :after_destroy callbacks or any dependent association options.
User.delete_all(condition:...
How do I run a program with a different working directory from current, from Linux shell?
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edited May 23 '17 at 11:33
Community♦
111 silver badge
answered Apr 24 '09 at 15:46
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What is the lifetime of a static variable in a C++ function?
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264
The lifetime of function static variables begins the first time[0] the program flow encounters...
How to modify a text file?
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edited Oct 9 '12 at 12:11
user229044♦
202k3535 gold badges298298 silver badges309309 bronze badges
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Add a property to a JavaScript object using a variable as the name?
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kube
8,60977 gold badges2727 silver badges3737 bronze badges
answered Mar 29 '09 at 18:02
Christian C. SalvadóChristian C. S...
Skip first entry in for loop in python?
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278
The other answers only work for a sequence.
For any iterable, to skip the first item:
iterca...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...eated if it wasn't done that way.
This way you can write fast code using 32-bit values in 64-bit mode without having to explicitly break dependencies all the time. Without this behaviour, every single 32-bit instruction in 64-bit mode would have to wait on something that happened before, even thoug...
What is the direction of stack growth in most modern systems?
...d you not (but still down, at least for zLinux).
ARM: selectable, but Thumb2 has compact encodings only for down (LDMIA = increment after, STMDB = decrement before).
6502: down (but only 256 bytes).
RCA 1802A: any way you want, subject to SCRT implementation.
PDP11: down.
8051: up.
Showing my ag...
postgresql return 0 if returned value is null
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182
use coalesce
COALESCE(value [, ...])
The COALESCE function returns the first of its argument...