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mongodb count num of distinct values per field/key
...}
},
{ $unwind: "$keywords" },
{
$group: {
_id: {$toLower: '$keywords'},
count: { $sum: 1 }
}
},
{
$match: {
count: { $gte: 2 }
}
},
{ $sort : { count : -1} },
{ $limit : 100 }
]);
that give result ...
Executing multi-line statements in the one-line command-line?
...
The issue is not actually with the import statement, it's with anything being before the for loop. Or more specifically, anything appearing before an inlined block.
For example, these all work:
python -c "import sys; print 'rob'"
python -c "imp...
“PKIX path building failed” and “unable to find valid certification path to requested target”
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Note that instructions should be repeated for all certificates in the chain. Also certificate's alias name in command line should be unique.
– Lu55
Sep 12 '17 at 18:50
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Custom exception type
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This will not allow you stack traces unless you inherit from Error
– Luke H
Jul 30 '14 at 19:53
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Mock functions in Go
I'm puzzled with dependencies. I want to be able to replace some function calls with mock ones. Here's a snippet of my code:
...
How to delete all the rows in a table using Eloquent?
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The reason MyModel::all()->delete() doesn't work is because all() actually fires off the query and returns a collection of Eloquent objects.
You can make use of the truncate method, this works for Laravel 4 and 5:
MyModel::truncate();
Th...
php stdClass to array
...g functions). "But I already did this" you say. Not exactly - you used json_decode on the array, but you need to encode it with json_encode first.
Requirements
The json_encode and json_decode methods. These are automatically bundled in PHP 5.2.0 and up. If you use any older version there's also a ...
How to copy an object in Objective-C
...deep, logical copy. In this, we make a copy of the object, but without actually doing it bit by bit - we want an object that behaves the same for all intents and purposes, but isn't (necessarily) a memory-identical clone of the original - the Objective C manual calls such an object "functionally ind...
std::mutex 加锁抛 _DEVICE_OR_RESOURCE_BUSY 异常 - C/C++ - 清泛网 - 专注C/C++及内核技术
std::mutex 加锁抛 _DEVICE_OR_RESOURCE_BUSY 异常device_or_resource_busy最近遇到一个崩溃，在 std::lock_guard<std::mutex> lock(mutex_); 的地方，抛出了_DEVICE_OR_RESOURCE_BUSY 的异常。最终查出原因是：同一个线程对同一个mutex二次加锁导致的 最近遇到...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个st...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个std::move编译报错日志如下： usr include c++ 4 7 bits stl_construct h:77:7: error: use of deleted function & 39;std::unique_ptr<_Tp, _Dp>::unique_ptr(const std::unique_p 编译报错日志如下：
/usr/...