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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
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How to get the full path of running process?
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According to my measurements, calling process.Modules[0] is 50 times slower than calling process.MainModule.
– Luca Cremonesi
Oct 23 '14 at 16:14
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How to read a file into a variable in shell?
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Ok but it's bash, not sh; it may not fit all cases.
– moala
Apr 15 '13 at 11:25
18
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How to pick just one item from a generator?
... would use the second syntax given in my answer, next(g). This will internally call g.__next__(), but you don't really have to worry about that, just as you usually don't care that len(a) internally calls a.__len__().
– Sven Marnach
Apr 10 '14 at 10:31
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Efficiently convert rows to columns in sql server
...d than just a single script but gives you much more flexibility.
First of all There are 3 objects:
User defined TABLE type [ColumnActionList] -> holds data as
parameter
SP [proc_PivotPrepare] -> prepares our data
SP [proc_PivotExecute] -> execute the script
CREATE TYPE [dbo].[ColumnAc...
How to find memory leak in a C++ code/project?
...e software tools
1
Understand the operator basics. The C++ operator new allocates heap memory. The delete operator frees heap memory. For every new, you should use a delete so that you free the same memory you allocated:
char* str = new char [30]; // Allocate 30 bytes to house a string.
delete ...
python setup.py uninstall
I have installed a python package with python setup.py install .
16 Answers
16
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Types in MySQL: BigInt(20) vs Int(20)
...gInt , MediumInt , and Int are... it would seem obvious that they would allow for larger numbers; however, I can make an Int(20) or a BigInt(20) and that would make seem that it is not necessarily about size.
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Rails Root directory path?
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Personally I like the newer syntax: Rails.root / 'app' / 'assets' / 'images' / 'logo.png'
– Ajedi32
Feb 18 '16 at 17:13
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node.js require all files in a folder?
How do I require all files in a folder in node.js?
14 Answers
14
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