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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...gsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function approach over that any day.
This works for single row, or few row, values. If you're deali...
In Scala, what exactly does 'val a: A = _' (underscore) mean?
....0d if T is Double,
false if T is Boolean,
() if T is Unit,
null for all other types T.
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Is there a performance impact when calling ToList()?
...mall the size is doubled so the backing array grows like this 4, 8, 16, 32 etc. Every time the backing array grows it has to be reallocated and all elements stored so far have to be copied. This operation is much more costly compared to the first case where an array of the correct size can be create...
WordPress is giving me 404 page not found for all pages except the homepage
...sts and the httpd.conf should be correct.
In my case, I changed the file /etc/apache2/apache2.conf in section:
<Directory "/var/www/html">
Line changed is:
AllowOverride None
to
AllowOverride All
And restart the web server with
systemctl restart apache2
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How can I search for a multiline pattern in a file?
I needed to find all the files that contained a specific string pattern. The first solution that comes to mind is using find piped with xargs grep :
...
Is there any standard for JSON API response format?
...). Define a uniform structure for errors (ex: code, message, reason, type, etc) and use it for errors, if it is a success then just return the expected json response.
Pros: Still standard as you use the existing HTTP status codes and you return a json describing the error (you provide more informa...
How do you add swap to an EC2 instance?
...something higher.
To enable it by default after reboot, add this line to /etc/fstab:
/var/swap.1 swap swap defaults 0 0
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How can I see the size of files and directories in linux? [closed]
... @FranciscoCorralesMorales ls -lh will show you the size in kb MB GB etc.
– mk..
Aug 5 '15 at 3:25
4
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find vs find_by vs where
...
Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
how to install gcc on windows 7 machine?
...for the downloads you need:
Binutils is the linker and resource compiler etc.
GCC is the compiler, and is split in core and language packages
GDB is the debugger.
runtime library is required only for mingw.org
You might need to download mingw32-make seperately.
For support, you can try (don't expe...