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Counting null and non-null values in a single query
... Using the distinction between count(*) and count(a) also works well with group by
– shannon
Mar 4 '15 at 7:36
1
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Simple explanation of clojure protocols
...dy have Multimethods?
The main thing Protocols offer over Multimethods is Grouping: you can group multiple functions together and say "these 3 functions together form Protocol Foo". You cannot do that with Multimethods, they always stand on their own. For example, you could declare that a Stack Pro...
How to check the version of GitLab?
...L: https://your.hostname
HTTP Clone URL: https://your.hostname/some-group/some-project.git
SSH Clone URL: git@your.hostname:some-group/some-project.git
Using LDAP: yes
Using Omniauth: no
GitLab Shell
Version: 2.6.8
Repositories: /var/opt/gitlab/git-data/repositories
Hooks: /opt/gi...
AngularJS: How to clear query parameters in the URL?
...om AngularJS forum. See this thread for details
The link is to a Google Groups thread, which is difficult to read and doesn't provide a clear answer. To remove URL parameters use
$location.url($location.path());
share
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Batch script: how to check for admin rights
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Doesn't work for the Domain Admins Group added to Administrators Group in the local machine and login with the domain Admin user.
– M.C.Rohith
Jan 17 '13 at 10:00
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Conditionally use 32/64 bit reference when building in Visual Studio
...o the project, open the .csproj in a text editor. Before the first <ItemGroup> element within the <Project> element, add the following code, which will help determine which platform you're running (and building) on.
<!-- Properties group for Determining 64bit Architecture -->
<...
ggplot2 plot without axes, legends, etc
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Many thanks! I also found a similar solution at groups.google.com/group/ggplot2/browse_thread/thread/…
– user1320487
Jul 1 '11 at 20:44
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Activity has leaked ServiceConnection @438030a8 that was original
... As the Activity doc tries to explain, there are three main bind/unbind
groupings you will use: onCreate() and onDestroy(), onStart() and
onStop(), and onResume() and onPause().
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improv...
What is the difference between Elastic Beanstalk and CloudFormation for a .NET project?
...ts away the underlying EC2 instances, Elastic Load Balancers, auto scaling groups, etc. This makes it a lot easier for developers, who don't want to be dealing with all the systems stuff, to get their application quickly deployed on AWS. It's very similar to other PaaS products such as Heroku, Eng...
Why is spawning threads in Java EE container discouraged?
...riority or name.
The enterprise bean must not attempt
to manage thread groups.
The reason is that EJBs are meant to operate in a distributed environment. An EJB might be moved from one machine in a cluster to another. Threads (and sockets and other restricted facilities) are a significant ba...