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Appropriate datatype for holding percent values?
..., the data type you use depends on how you plan to store your percentages. If you are going to store their fractional equivalent (e.g. 100.00% stored as 1.0000), I would store the data in a decimal(5,4) data type with a CHECK constraint that ensures that the values never exceed 1.0000 (assuming that...
Vagrant's port forwarding not working [closed]
...omments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that there are no fir...
HttpServletRequest to complete URL
...URL().toString());
String queryString = request.getQueryString();
if (queryString == null) {
return requestURL.toString();
} else {
return requestURL.append('?').append(queryString).toString();
}
}
...
Postgis installation: type “geometry” does not exist
...
Thanks. BTW, If someone using 'psql' to run this code, make sure the role have 'Superuser' attribute/privilege.
– Yang
Dec 12 '15 at 3:09
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What is the difference between sites-enabled and sites-available directory?
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The difference is that virtual sites listed in the sites-enabled directory are served by apache. In the sites-available directory there are the virtual sites that exist on your server but people can't access them because they are ...
Maximum packet size for a TCP connection
...ld use a lower one. With the advent of jumbo frames, there is no real specified maximum, and the maximum varies depending on the hardware and driver.
– WhirlWind
Apr 10 '10 at 17:08
...
Debug vs. Release performance
...piled at all
some loop variables are taken out of the loop by the compiler if they are proven to be invariants
code written under #debug directive is not included, etc.
The rest is up to the JIT.
Full list of optimizations here courtesy of Eric Lippert.
...
PostgreSQL - max number of parameters in “IN” clause?
In Postgres, you can specify an IN clause, like this:
8 Answers
8
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Maintain/Save/Restore scroll position when returning to a ListView
...isible list item. But this item may be partially scrolled out of view, and if you want to restore the exact scroll position of the list you need to get this offset. So ListView.getChildAt(0) returns the View for the top list item, and then View.getTop() - mList.getPaddingTop() returns its relative o...
Getting the first index of an object
...
If the order of the objects is significant, you should revise your JSON schema to store the objects in an array:
[
{"name":"foo", ...},
{"name":"bar", ...},
{"name":"baz", ...}
]
or maybe:
[
["foo", {}],
...