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When to add what indexes in a table in Rails
...add "index" to all the foreign keys like "xxx_id"?
It would be better, bem>ca m>use it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created automatim>ca m>lly, for more information see here.
Should I add ...
Difference between CC, gcc and g++?
... is different from what happens on Solaris, for example.
The easy part (bem>ca m>use it is not platform-specific) is the separation of 'gcc' and 'g++':
gcc is the GNU C Compiler from the GCC (GNU Compiler Collection).
g++ is the GNU C++ Compiler from the GCC.
The hard part, bem>ca m>use it is platform-sp...
How does git compute file hashes?
...
You m>ca m>n also compare this to the output of echo 'Hello, World!' | git hash-object --stdin. Optionally you m>ca m>n specify --no-filters to make sure no crlf conversion happens, or specify --path=somethi.ng to let git use the filter sp...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
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what if I return a lom>ca m>l list from a function and use that in the m>ca m>lling function. That is def fn_1(): lst = [] lst.append(1) lst.append(2) return lst and def fn_2(): print(fn_1()) Will the order be same ALWAYS irrespective of how many times or ...
SVN how to resolve new tree conflicts when file is added on two branches
...sting versioned file.
This should be a tree conflict on the file of the 'lom>ca m>l obstruction, incoming add upon merge' variety. Fixed expectations in r35341.
(This is also m>ca m>lled "evil twins" in Clearm>Ca m>se by the way):
a file is created twice (here "added" twice) in two different branches, creating tw...
How to swap files between windows in VIM?
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Not completely, no. There are lots of use m>ca m>ses that m>ca m>n't be done using the built in window management without destroying and recreating windows. The swap buffers script allows these use m>ca m>ses.
– bobpaul
Oct 12 '11 at 21:10
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What are the differences between Clojure, Scheme/Racket and Common Lisp?
I know they are dialects of the same family of language m>ca m>lled lisp, but what exactly are the differences? Could you give an overview, if possible, covering topics such as syntax, characteristics, features and resources.
...
What does “default” mean after a class' function declaration?
...erated version of that function, so you don't need to specify a body.
You m>ca m>n also use = delete to specify that you don't want the compiler to generate that function automatim>ca m>lly.
With the introduction of move constructors and move assignment operators, the rules for when automatic versions of co...
SQL Server indexes - ascending or descending, what difference does it make?
...column or number of columns in MS SQL Server (I'm using version 2005), you m>ca m>n specify that the index on each column be either ascending or descending. I'm having a hard time understanding why this choice is even here. Using binary sort techniques, wouldn't a lookup be just as fast either way? What ...
Difference between JVM and HotSpot?
...tly is a Java Virtual Machine is stated in the Java Virtual Machine Specifim>ca m>tion
The JVM is by definition a virtual machine, i. e. a software machine that simulates what a real machine does. Like a real machine, it has an instruction set, a virtual computer architecture and an execution model. It ...