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Rails - Nested includes on Active Records?
...
how to add there a order?
– Florian Widtmann
Jan 12 '16 at 7:49
6
...
List columns with indexes in PostgreSQL
...um = ANY(ix.indkey)
and t.relkind = 'r'
and t.relname like 'test%'
order by
t.relname,
i.relname;
table_name | index_name | column_name
------------+------------+-------------
test | pk_test | a
test | pk_test | b
test2 | uk_test2 | b
test2 | uk_te...
Compile error: “g++: error trying to exec 'cc1plus': execvp: No such file or directory”
...grep gcc | awk '{print $2}'
Usually, /usr/bin/gcc will be sym-linked to /etc/alternatives/gcc which is again sym-linked to say /usr/bin/gcc-4.6 or /usr/bin/gcc-4.8 (In case you have gcc-4.6, gcc-4.8 installed.)
By changing this link you can make gcc and g++ run in the same version and this may r...
What is “callback hell” and how and why does RX solve it?
...e from event handling code. You can easily handle details like async event ordering that are a nightmare when using state variables. I found RX was the cleanest implementation to perform a new network request after 3 network responses returned or to error handle the whole chain if one does not retur...
How to format strings in Java
...od, so you just have to pass the restURL like this
/customer/{0}/user/{1}/order
and add as many params as you need:
public String createURL (String restURL, Object ... params) {
return new MessageFormat(restURL).format(params);
}
You just have to call this method like this:
createU...
Regex - Should hyphens be escaped? [duplicate]
...er in the range (e.g. [-a-z] or [0-9-]), OR escape it (e.g. [a-z\-0-9]) in order to add "hyphen" to your class.
It's more common to find a hyphen placed first or last within a character class, but by no means will you be lynched by hordes of furious neckbeards for choosing to escape it instead.
(A...
“Use the new keyword if hiding was intended” warning
...ace IShow and implements its method ShowData. Class B inherits Class A. In order to use ShowData method in Class B, we have to use keyword new in the ShowData method in order to hide the base class Class A method and use override keyword in order to extend the method.
interface IShow
{
protect...
Backwards migration with Django South
...en you run ./manage.py migrate your_app, South runs all new migrations, in order. (It looks at the database tables to decide which ones are 'new').
However, you can also specify any migration by number, and South will migrate your database, either forward or backward, to take it to that point. So, ...
apache redirect from non www to www
...put www. in the ServerAlias using the *. wildcard. Because I messed up the ordering of the VirtualHost entries, the *. wildcard had the opportunity to match when I didn't think it would.
– dmiller309
May 10 '14 at 21:28
...
MySQL DISTINCT on a GROUP_CONCAT()
...UP_CONCAT has DISTINCT attribute:
SELECT GROUP_CONCAT(DISTINCT categories ORDER BY categories ASC SEPARATOR ' ') FROM table
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