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...rticle. Pythons hashing algorithms are explained on effbot.org and pythons __hash__ function in the python reference.
Some facts:
Set elements as well as dictionary keys have to be hashable
Some unhashable datatypes:
list: use tuple instead
set: use frozenset instead
dict: has no official count...
Is it possible to GROUP BY multiple columns using MySQL?
...y the rows are sorted.
In your example, you would write
GROUP BY fV.tier_id, f.form_template_id
Meanwhile, the code
GROUP BY f.form_template_id, fV.tier_id
would give similar results, but sorted differently.
share
...
Safely remove migration In Laravel
...teps:
Manually delete the migration file under app/database/migrations/my_migration_file_name.php
Reset the composer autoload files: composer dump-autoload
Relax
If you did run the migration (php artisan migrate), you may do this:
a) Run migrate:rollback - it is the right way to undo the last...
Putting git hooks into repository
...sh
if [ -x $0.local ]; then
$0.local "$@" || exit $?
fi
if [ -x tracked_hooks/$(basename $0) ]; then
tracked_hooks/$(basename $0) "$@" || exit $?
fi
The installation script would move all pre-existing hooks to the side (append .local to their names), and symlink all known hook names to the...
Backwards migration with Django South
...r app should have a migrations directory, with files in it named like
0000_initial.py
0001_added_some_fields.py
0002_added_some_more_fields.py
0003_deleted_some_stuff.py
Normally, when you run ./manage.py migrate your_app, South runs all new migrations, in order. (It looks at the database tables ...
Mixin vs inheritance
...dited Jun 21 at 11:36
underscore_d
4,91633 gold badges2828 silver badges5454 bronze badges
answered May 13 '09 at 20:42
...
How To Change DataType of a DataColumn in a DataTable?
...newType)
{
using (DataColumn dc = new DataColumn(columnName + "_new", newType))
{
// Add the new column which has the new type, and move it to the ordinal of the old column
int ordinal = dt.Columns[columnName].Ordinal;
dt.Columns.Add(dc);
...
Find the most common element in a list
...ponents. Consider for example:
import itertools
import operator
def most_common(L):
# get an iterable of (item, iterable) pairs
SL = sorted((x, i) for i, x in enumerate(L))
# print 'SL:', SL
groups = itertools.groupby(SL, key=operator.itemgetter(0))
# auxiliary function to get "quality"...
Where do I set my company name?
...
If you want change __MyCompanyName__ in Xcode 4, you can try the following command.
defaults write com.apple.dt.Xcode PBXCustomTemplateMacroDefinitions '{ORGANIZATIONNAME="YourNameHere";}'
Carefully, this writes in the domain, com.apple.dt.Xc...
Difference between assertEquals and assertSame in phpunit?
...ly about an interpreted value, be it by type juggling or an object with an __magic presentation method (__toString() for example).
A good use case for assertSame() is testing a singleton factory.
class CacheFactoryTest extends TestCase
{
public function testThatCacheFactoryReturnsSingletons()
...