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Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
...
How exactly does a generator comprehension work?
... generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my_list = [1, 3, 5, 9, 2, 6]
>>> filtered_list = [item for item in my_list i...
How to debug heap corruption errors?
...nctionality was in Application Verifier.
Electric Fence (aka "efence"), dmalloc, valgrind, and so forth are all worth mentioning, but most of these are much easier to get running under *nix than Windows. Valgrind is ridiculously flexible: I've debugged large server software with many heap issues u...
Where is a complete example of logging.config.dictConfig?
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All those concise, beautiful YAML snippets in the python logging.config docs just can't be read directly. Bummer.
– JimB
May 17 '18 at 18:19
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Database, Table and Column Naming Conventions? [closed]
... for Primary Key Columns, Hungarian-esque Constraint Prefixes and worst of all SPACES " " for multi-word table names. Additionally system tables for SQLServer use plurals so it seems AdventureWorks was the black sheep in this bunch.
– Marcus Pope
Mar 20 '12 at...
Dynamically updating plot in matplotlib
...out the more modern animation examples in the matplotlib documentation. Finally, the animation API defines a function FuncAnimation which animates a function in time. This function could just be the function you use to acquire your data.
Each method basically sets the data property of the object be...
How to reset db in Django? I get a command 'reset' not found error
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It looks like the 'flush' answer will work for some, but not all cases. I needed not just to flush the values in the database, but to recreate the tables properly. I'm not using migrations yet (early days) so I really needed to drop all the tables.
Two ways I've found to drop all ...
Tracking Google Analytics Page Views with AngularJS
...cs does not count it as a new page load. Fortunately there is a way to manually tell GA to log a url as a new pageview.
_gaq.push(['_trackPageview', '<url>']); would do the job, but how to bind that with AngularJS?
Here is a service which you could use:
(function(angular) {
angular.modu...
Test PHP headers with PHPUnit
...78
Error: Class 'PHPUnit_Util_Configuration' not found in - on line 378
Call Stack:
0.0013 582512 1. {main}() -:0
Try add this to your bootstrap file to fix it:
<?php
if (!defined('PHPUNIT_COMPOSER_INSTALL')) {
define('PHPUNIT_COMPOSER_INSTALL', __DIR__ . '/path/to/composer/ven...
Android SDK installation doesn't find JDK
I'm trying to install the Android SDK on my Windows 7 x64 System.
45 Answers
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