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Java's L number (long) specification

It appears that when you type in a number in Java, the compiler automatically reads it as an integer, which is why when you type in (long) 6000000000 (not in integer's range) it will complain that 6000000000 is not an integer. To correct this, I had to specify 6000000000L . I just learned abo...
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Read file from line 2 or skip header row

... This is fine UNTIL the file is too large to read. This is fine for small files. – CppLearner Feb 5 '18 at 2:05 1 ...
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How does collections.defaultdict work?

... Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
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Combining two expressions (Expression)

...m); } Starting from .NET 4.0, there is the ExpressionVisitor class which allows you to build expressions that are EF safe. public static Expression<Func<T, bool>> AndAlso<T>( this Expression<Func<T, bool>> expr1, Expression<Func<T, bool>&...
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How can I cast int to enum?

... (e.g. "2342342" -- assuming that's not a value of your enum), it will actually allow that without throwing an error! Your enum will have that value (2342342) even though it's not a valid choice in the enum itself. – JoeCool Jun 25 '13 at 15:14 ...
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How to reset db in Django? I get a command 'reset' not found error

... 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 ...
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Django: How to manage development and production settings?

...s you define environment variables in an "environment" (.env) file. Finally, note that you can take advantage of the PYTHONPATH variable to store the settings in a completely different location (e.g. on a production server, storing them in /etc/). This allows for separating configuration from ap...
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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. ...
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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...
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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...