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Fastest Way to Find Distance Between Two Lat/Long Points
...s of Geometry data types in MyISAM table. As of Mysql 5.7.5, InnoDB tables now also support SPATIAL indices.
Create a SPATIAL index on these points
Use MBRContains() to find the values:
SELECT *
FROM table
WHERE MBRContains(LineFromText(CONCAT(
'('
, @lon + 10 / ( 111.1 / cos...
Understanding the Gemfile.lock file
...ck in the application together with the Gemfile and Gemfile.lock snapshot. Now, your repository has a record of the exact versions of all of the gems that you used the last time you know for sure that the application worked...
This is important: the Gemfile.lock makes your application a single packa...
How to write a JSON file in C#?
...nd a couple of key places where object allocations could be reduced...... (now) Json.Net (6.0) allocates 8 times less memory than JavaScriptSerializer
Update since .Net Core 3.0
A new kid on the block since writing this is System.Text.Json which has been added to .Net Core 3.0. Microsoft mak...
Difference between java.util.Random and java.security.SecureRandom
...l purposes. This also means that your random numbers are predictable right now, something you don't want for session IDs and the like.
How to break a Linear Congruential Generator
The assumption that an attacker would have to wait for the LCG to repeat after a full cycle is wrong. Even with an opt...
Best way to structure a tkinter application? [closed]
...
@Bryan Oakley do you know any good sample codes on internet that i can study their structure?
– Chris Aung
Jul 5 '13 at 8:35
3
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Django using get_user_model vs settings.AUTH_USER_MODEL
...eignKey/ManyToMany-relation.
From the changelog:
get_user_model() can now be called at import time, even in modules that define models.
so... is there still a reason to use settings.AUTH_USER_MODEL? Well, the docs still recommend the settings.AUTH_USER_MODEL (which is a string) for defining r...
First-time database design: am I overengineering? [closed]
...
1. Thanks, that's reassuring! 2 & 3. I still don't know how indexes work, it's something I have planned to read up on. If we ever have the "problem" of reaching a million records there will probably be a budget to hire experienced developers :P Thanks for the insight into diff...
Transferring an app to another Firebase account
I have a few apps under my personal firebase account for testing, but now need to transfer an app to a client's account for billing purposes. Is this possible?
...
How to convert a Git shallow clone to a full clone?
...
EDIT: git fetch --unshallow now is an option (thanks Jack O'Connor).
You can run git fetch --depth=1000000 (assuming the repository has less than one million commits).
share
...
How JavaScript closures are garbage collected
...ndow.f_ = f();
window.f_('some');
In example above the GC has no way of knowing if the variable is used or not (code tested and works in Chrome30, FF25, Opera 12 and IE10).
The memory is released if the reference to the object is broken by assigning another value to window.f_.
In my opinion this...