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postgresql return 0 if returned value is null
...M. In this example, if we replace AVG by SUM, the result is not distorted. Adding 0 to a sum doesn't hurt anyone but calculating an average with 0 for the unknown values, you don't get the real average.
In that case, I would add price IS NOT NULL in WHERE clause to avoid these unknown values.
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Applying a git post-commit hook to all current and future repos
...written a Git post-commit hook and it works correctly. However, I want to add this hook to apply to all current (and future) git repositories I am working on. I tried adding the hook to my ~/.git/hooks/ instead of in the hooks directory in the project directory, however, this did not seem to wor...
400 vs 422 response to POST of data
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400 Bad Request would now seem to be the best HTTP/1.1 status code for your use case.
At the time of your question (and my original answer), RFC 7231 was not a thing; at which point I objected to 400 Bad Request because RFC 2616 ...
What is a semaphore?
...aphore is a programming concept that is frequently used to solve multi-threading problems. My question to the community:
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@RequestBody and @ResponseBody annotations in Spring
...tion. I suggest you consult those sections. Also relevant: @RequestBody javadocs, @ResponseBody javadocs
Usage examples would be something like this:
Using a JavaScript-library like JQuery, you would post a JSON-Object like this:
{ "firstName" : "Elmer", "lastName" : "Fudd" }
Your controller me...
Set a persistent environment variable from cmd.exe
... an env var "foo" with value of "bar":
setx foo bar
Though it's worth reading the 'notes' that are displayed if you print the usage (setx /?), in particular:
2) On a local system, variables created or modified by this tool will be available in future command windows but not in the current CMD...
Why we should not use protected static in java
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The only case I can see where you might use the two together is if you had an abstract class that was designed to be extended and the extending class could then modify the behavior using constants defined in the original. That sort of arrangement would most likely end up very messy though and ind...
How do I pull my project from github?
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Alice Purcell
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answered Sep 11 '09 at 3:15
SantiSanti
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Spring Boot application as a Service
...d service
To run a Spring Boot application installed in var/myapp you can add the following script in /etc/systemd/system/myapp.service:
[Unit]
Description=myapp
After=syslog.target
[Service]
ExecStart=/var/myapp/myapp.jar
[Install]
WantedBy=multi-user.target
NB: in case you are using this m...
Static function variables in Swift
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Honey
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answered Aug 18 '14 at 0:28
Bryan ChenBryan Chen
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