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SQLite table constraint - unique on multiple columns
... adding UNIQUE(i, j) to the create statement is completely ignored on android. It creates the table, but leaves off the UNIQUE constraint. I was only able to do this by using an index.
– gattsbr
Aug 11 at 14:55
...
How to query as GROUP BY in django?
...ike aggregating lines_count=Count('lines'))).
Over a queryset qs you can call qs.query.group_by = ['field1', 'field2', ...] but it is risky if you don't know what query are you editing and have no guarantee that it will work and not break internals of the QuerySet object. Besides, it is an interna...
Is there a `pointer-events:hoverOnly` or similar in CSS?
... it's easy enough to do in JQuery. Here's how I've done it:
HTML
<div
id="toplayer"
class="layer"
style="
z-index: 20;
pointer-events: none;
background-color: white;
display: none;
"
>
Top layer
</div>
<div id="bottomlayer" class="layer" style="z-index: 10"&g...
How to convert SSH keypairs generated using PuTTYgen (Windows) into key-pairs used by ssh-agent and
...Export OpenSSH and export your private key
Copy your private key to ~/.ssh/id_dsa (or id_rsa).
Create the RFC 4716 version of the public key using ssh-keygen
ssh-keygen -e -f ~/.ssh/id_dsa > ~/.ssh/id_dsa_com.pub
Convert the RFC 4716 version of the public key to the OpenSSH format:
ssh-keygen ...
CSS Input Type Selectors - Possible to have an “or” or “not” syntax?
...
CSS3 has a pseudo-class called :not()
input:not([type='checkbox']) {
visibility: hidden;
}
<p>If <code>:not()</code> is supported, you'll only see the checkbox.</p>
<ul...
Magic number in boost::hash_combine
The boost::hash_combine template function takes a reference to a hash (called seed ) and an object v . According to the docs , it combines seed with the hash of v by
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Global variables in AngularJS
...alue. The problem with it is that the controller that initialises it, gets called again by angular some how and then resets the variable back to its initial value.
...
How do I get a distinct, ordered list of names from a DataTable using LINQ?
...lumn. I want to generate a collection of the unique names ordered alphabetically. The following query ignores the order by clause.
...
How to horizontally center a
...
You can apply this CSS to the inner <div>:
#inner {
width: 50%;
margin: 0 auto;
}
Of course, you don't have to set the width to 50%. Any width less than the containing <div> will work. The margin: 0 auto is what does the actual centering.
If you are targeting Internet...
How do I typedef a function pointer with the C++11 using syntax?
...
It has a similar syntax, except you remove the identifier from the pointer:
using FunctionPtr = void (*)();
Here is an Example
If you want to "take away the uglyness", try what Xeo suggested:
#include <type_traits>
using FunctionPtr = std::add_pointer<void(...