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Laravel Eloquent groupBy() AND also return count of each group
...
This is working for me:
$user_info = DB::table('usermetas')
->select('browser', DB::raw('count(*) as total'))
->groupBy('browser')
->get();
...
How can I add reflection to a C++ application?
...not managed C++, which has reflection. I realise C++ supplies some limited information using RTTI. Which additional libraries (or other techniques) could supply this information?
...
Getting time elapsed in Objective-C
...Date date] could lead to difficult to track bugs, see this answer for more info.
– Senseful
Aug 1 '13 at 6:43
@PinkFlo...
Logging levels - Logback - rule-of-thumb to assign log levels
...issue that needs to be tracked but may not require immediate intervention.
info: things we want to see at high volume in case we need to forensically analyze an issue. System lifecycle events (system start, stop) go here. "Session" lifecycle events (login, logout, etc.) go here. Significant bound...
What is the copy-and-swap idiom?
...d ready to be used. This is what gives us a strong exception guarantee for free: we won't even enter the function if construction of the copy fails, and it's therefore not possible to alter the state of *this. (What we did manually before for a strong exception guarantee, the compiler is doing for u...
Which maven dependencies to include for spring 3.0?
....1.2.RELEASE</version>
</dependency>
This will resolve to
[INFO] The following files have been resolved:
[INFO] aopalliance:aopalliance:jar:1.0:compile
[INFO] commons-logging:commons-logging:jar:1.1.1:compile
[INFO] org.springframework:spring-aop:jar:3.1.2.RELEASE:compile
[I...
App Inventor 2 FTP 客户端拓展：FTP协议连接、上传、下载、创建、修改目录...
...略和使用条款 关注公众号，精彩不错过！ #free_v { border:none; position:fixed; top:40%; left:5px; width:200px; height:500px; display: none;}@media screen and (max-width: 700px) { #free_v { top:200%; }}
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...set should be
inversely proportional to the square root of the number of free
adjustable parameters.
In their conclusion they specify a formula:
Validation set (v) to training set (t) size ratio, v/t, scales like
ln(N/h-max), where N is the number of families of recognizers and
h-max i...
App Inventor 2 拓展参考文档 · App Inventor 2 中文网
...略和使用条款 关注公众号，精彩不错过！ #free_v { border:none; position:fixed; top:40%; left:5px; width:200px; height:500px; display: none;}@media screen and (max-width: 700px) { #free_v { top:200%; }}
How do I restart a WPF application? [duplicate]
...NetworkDeployed will be false when you restart. See bit.ly/RKoVBz for more info. If your application is not deployed with ClickOnce, this method works great.
– blachniet
Oct 21 '12 at 14:17
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