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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ou're on 9.5 and don't need to be backward-compatible you can stop reading now.
9.4 and older:
PostgreSQL doesn't have any built-in UPSERT (or MERGE) facility, and doing it efficiently in the face of concurrent use is very difficult.
This article discusses the problem in useful detail.
In general y...
Error when trying vagrant up
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Gar, that was it. Why does it say "You are now ready to vagrant up your first virtual environment!" then??
– Matt
Jun 30 '15 at 21:55
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Switch branch names in git
...ed from before I started my crap work. Practically this works fine, I just now have a different branch as my main development branch. I'm wondering how I could change things around so I'm working on master again but it doesn't have my junk work and said work is on a different branch.
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Multiple glibc libraries on a single host
...of glibc on the same system (we do that every day).
However, you need to know that glibc consists of many pieces (200+ shared libraries) which all must match. One of the pieces is ld-linux.so.2, and it must match libc.so.6, or you'll see the errors you are seeing.
The absolute path to ld-linux.so....
How to write a bash script that takes optional input arguments?
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you need write to a regular variable to use the substitution
#!/bin/bash
NOW=$1
echo ${NOW:-$(date +"%Y-%m-%d")}
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What does “./bin/www” do in Express 4.x?
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Because the app.js file that was generated by the Express 4 generator is now a Node.js module, it can no longer be started independently as an app (unless you modify the code). The module must be loaded in a Node.js file and started via the Node.js file. The Node.js file is ./bin/www in this case....
What is the difference between location list and quickfix list in vim
...us to move through those lists without opening the associated windows and knowing the difference between those lists is key to using those commands efficiently.
Hands-on illustrated example:
Do :lvim foo % in foo.txt to create a location list for the window containing foo.txt.
Do :lne a few ti...
Moment.js - how do I get the number of years since a date, not rounded up?
...on's age using Moment.js , but I'm finding that the otherwise useful fromNow method rounds up the years. For instance, if today is 12/27/2012 and the person's birth date is 02/26/1978, moment("02/26/1978", "MM/DD/YYYY").fromNow() returns '35 years ago'. How can I make Moment.js ignore the numbe...
“Large data” work flows using pandas
... store.append(g, frame, index=False, data_columns = v['dc'])
Now you have all of the tables in the file (actually you could store them in separate files if you wish, you would prob have to add the filename to the group_map, but probably this isn't necessary).
This is how you get colum...
How to return an empty ActiveRecord relation?
...and it takes an argument, depending on the value of the argument, I might know that there will not be any matches, but I still want to return a relation, not an empty array:
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