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How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
...
PyPy — How can it possibly beat CPython?
... an object can save you the need to do multiple pointer dereferences to finally arrive at the method you want to call.
Q2. Which Python implementation was used to implement PyPy?
The PyPy interpreter is implemented in RPython which is a statically typed subset of Python (the language and not the ...
How to remove all null elements from a ArrayList or String Array?
...
Try:
tourists.removeAll(Collections.singleton(null));
Read the Java API. The code will throw java.lang.UnsupportedOperationException for immutable lists (such as created with Arrays.asList); see this answer for more details.
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CUDA incompatible with my gcc version
... If you compile with cmake .. && make you can try cmake -D CUDA_NVCC_FLAGS="-ccbin gcc-4.4" .. && make. If you use plain Makefile you can try make CXX=g++-4.4 CC=gcc-4.4.
– patryk.beza
Apr 4 '16 at 18:54
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How to strip all non-alphabetic characters from string in SQL Server?
How could you remove all characters that are not alphabetic from a string?
18 Answers
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gulp globbing- how to watch everything below directory
This is a pretty dumb question, but I haven't really been able to find a satisfactory answer: How do I use gulp globbing to select all files in all subdirectories below a certain directory?
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How to split long commands over multiple lines in PowerShell
...loy.exe" `
-verb:sync `
-source:contentPath="c:\workspace\xxx\master\Build\_PublishedWebsites\xxx.Web" `
-dest:contentPath="c:\websites\xxx\wwwroot,computerName=192.168.1.1,username=administrator,password=xxx"
White space matters. The required format is Space`Enter.
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Parallelize Bash script with maximum number of processes
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With GNU Parallel http://www.gnu.org/software/parallel/ you can write:
some-command | parallel do-something
GNU Parallel also supports running jobs on remote computers. This will run one per CPU core on the remote computers - even if ...
How to add a button to UINavigationBar?
...= CGRectMake(0, 0, 32, 32);
[button setImage:[UIImage imageNamed:@"settings_b.png"] forState:UIControlStateNormal];
[button addTarget:self action:@selector(openView) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barButton=[[UIBarButtonItem alloc] init];
[barButton setCustomView:bu...
How to define a two-dimensional array?
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You're technically trying to index an uninitialized array. You have to first initialize the outer list with lists before adding items; Python calls this
"list comprehension".
# Creates a list containing 5 lists, each of 8 items, all set t...