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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
... CONFLICT (key) DO UPDATE (and ON CONFLICT (key) DO NOTHING), i.e. upsert.
Comparison with ON DUPLICATE KEY UPDATE.
Quick explanation.
For usage see the manual - specifically the conflict_action clause in the syntax diagram, and the explanatory text.
Unlike the solutions for 9.4 and older that are g...
Why is there a difference in checking null against a value in VB.NET and C#?
...de different assumptions about usage; in this case the semantics of a NULL comparison.
My personal preference is for the VB.NET semantics, which in essence gives NULL the semantics "I don't know yet". Then the comparison of 5 to "I don't know yet". is naturally "I don't know yet"; ie NULL. This has...
Declaration/definition of variables locations in ObjectiveC?
... your confusion. Especially since recent updates to Xcode and the new LLVM compiler changed the way ivars and properties can be declared.
Before "modern" Objective-C (in "old" Obj-C 2.0) you didn't have a lot of choices. Instance variables used to be declared in the header between the curly bracket...
How to apply a Git patch to a file with a different name and path?
I have two repositories. In one, I make changes to file ./hello.test . I commit the changes and create a patch from that commit with git format-patch -1 HEAD . Now, I have a second repository that contains a file that has the same contents as hello.test but is placed in a different directory under...
How do I tell Maven to use the latest version of a dependency?
...ke of reproducible builds", over 6 years ago.
Please refer to this Maven 3 compliant solution.
If you always want to use the newest version, Maven has two keywords you can use as an alternative to version ranges. You should use these options with care as you are no longer in control of the plugi...
Can I set the height of a div based on a percentage-based width? [duplicate]
...flowerblue;
margin: 25px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="dynamicheight"></div>
If you want the box to scale with the browser window on resize, move the code to a function and call it on the...
Difference between JAX-WS, Axis2 and CXF
... the JDK really is just the basic soap stuff. If you need any of the more complex WS-* things like WS-Security, WS-RM, WS-Policy, etc..., you need to use one of the alternatives like CXF or Metro or Axis2. It can also depend on what you are trying to integrate with. For example, CXF has top notc...
Forcing a WPF tooltip to stay on the screen
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