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Multiple ModelAdmins/views for same model in Django admin
...l may be registered only once.
class PostAdmin(admin.ModelAdmin):
list_display = ('title', 'pubdate','user')
class MyPost(Post):
class Meta:
proxy = True
class MyPostAdmin(PostAdmin):
def get_queryset(self, request):
return self.model.objects.filter(user = request.user...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an error. It generates a warning instead. These cases include:
Inserting a duplicate key in columns with PRIMARY KEY or UNIQUE constrain...
Count number of lines in a git repository
How would I count the total number of lines present in all the files in a git repository?
15 Answers
...
Stateless and Stateful Enterprise Java Beans
...s. If stateless session beans do not retain their state in between method calls, why is my program acting the way it is?
7 ...
Apply pandas function to column to create multiple new columns?
...
I usually do this using zip:
>>> df = pd.DataFrame([[i] for i in range(10)], columns=['num'])
>>> df
num
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
>>> def powers(x):
>...
How do I compare two hashes?
...=> [["c", 3]]
Hash[*difference.flatten]
=> {"c"=>3}
Doing it all in one operation and getting rid of the difference variable:
Hash[*(
(hash3.size > hash1.size) \
? hash3.to_a - hash1.to_a \
: hash1.to_a - hash3.to_a
).flatten]
=> {"c"=>3}
...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
...e is to assign a dummy column to separate each new table. This works especially well if you're looping through a result set for a list of columns in a scripting language such as Python or PHP.
SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table...
Is a LINQ statement faster than a 'foreach' loop?
...ting a Mesh Rendering manager and thought it would be a good idea to group all of the meshes which use the same shader and then render these while I'm in that shader pass.
...
Configuring Vim for C++
... abbreviations for my C++ use, for example :
abbreviate bptr boost::shared_ptr
abbreviate cstr const std::string &
I have several functions for "code snippets" like things, for example :
function! IncludeGuard()
let basename = expand("%:t:r")
let includeGuard = '__' . basename . '_h__'
...
JavaScript - get the first day of the week from current date
...
This is great except this function should be called "setToMonday" as it modifies the date object passed in. getMonday, would return a new Date that is the monday based on the date passed in. A subtle difference, but one that caught me after using this function. Easiest f...