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Rails :include vs. :joins
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.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again
:includes will eager load the included associations and add them in memory. :includes loads all the included tables attributes. If you call ...
Sort a single String in Java
...cuse for you at all. Your comment, and downvote, won't change anything for now. That's what I decided FOUR years ago, I don't see what's the point of bringing this up now :)
– Maroun
Apr 16 '18 at 8:13
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Django admin: how to sort by one of the custom list_display fields that has no database field
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I haven't tested this out (I'd be interested to know if it works) but what about defining a custom manager for Customer which includes the number of orders aggregated, and then setting admin_order_field to that aggregate, ie
from django.db import models
class CustomerManage...
Why am I getting an Exception with the message “Invalid setup on a non-virtual (overridable in VB) m
...ides the behaviors that you have set up in the "SetUp" method. And as you know in C#, you can override something only if it is marked as virtual which isn't the case with Java. Java assumes every non-static method to be virtual by default.
Another thing I believe you should consider is introducing ...
How to identify server IP address in PHP
How can I identify the server IP address in PHP?
15 Answers
15
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What's onCreate(Bundle savedInstanceState)
Can anyone help me to know about the Bundle savedInstanceState in onCreate(Bundle savedInstanceState) I am newbie in Android. I try to understand it from developer.android.com. But I am not able to understand. Can anyone simplify it?
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Change R default library path using .libPaths in Rprofile.site fails to work
...getenv())) ]
The two that matter for storing and accessing packages are (now different on a Linux box):
R_LIBS_SITE /usr/local/lib/R/site-library:/usr/lib/R/site-library:/usr/lib/R/library
R_LIBS_USER /home/david/R/x86_64-pc-linux-gnu-library/3.5....
Check if a user has scrolled to the bottom
...he .scroll() event on window, like this:
$(window).scroll(function() {
if($(window).scrollTop() + $(window).height() == $(document).height()) {
alert("bottom!");
}
});
You can test it here, this takes the top scroll of the window, so how much it's scrolled down, adds the height of th...
Convert string to symbol-able in ruby
...from string to symbol), and .to_s can convert (from symbol to string). and if you are dealing with an array consider .map(&:to_sym) or .map(&to_s) to convert all elements.
– jasonleonhard
Nov 5 '15 at 22:22
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How to change package name of an Android Application
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It does the same to me right now if I right-click on the root directory. At least for me, that's not my actual package name. If your package name is com.a.bc, there should be a directory below the root directory called bc. That's where you'll get the dif...