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How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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How to check if field is null or empty in MySQL?
...
If you would like to check in PHP , then you should do something like :
$query_s =mysql_query("SELECT YOURROWNAME from `YOURTABLENAME` where name = $name");
$ertom=mysql_fetch_array($query_s);
if ('' !== $ertom['YOURROWNAME']) {
//do your action
ech...
Using logging in multiple modules
I have a small python project that has the following structure -
11 Answers
11
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How to combine two or more querysets in a Django view?
...sets into a list is the simplest approach. If the database will be hit for all querysets anyway (e.g. because the result needs to be sorted), this won't add further cost.
from itertools import chain
result_list = list(chain(page_list, article_list, post_list))
Using itertools.chain is faster than...
How can I get all the request headers in Django?
I need to get all the Django request headers. From what i've read, Django simply dumps everything into the request.META variable along with a lot aof other data. What would be the best way to get all the headers that the client sent to my Django application?
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How do you detect Credit card type based on number?
...rds; there are other cards issued using the MasterCard system that do not fall into this IIN range. In 2016, they will add numbers in the range (222100-272099).
American Express: ^3[47][0-9]{5,}$ American Express card numbers start with 34 or 37.
Diners Club: ^3(?:0[0-5]|[68][0-9])[0-9]{4,}$ Dine...
C++ project organisation (with gtest, cmake and doxygen)
...rs are the
basis for users to interact with what you offer and must be
installed. This means they have to be in a subdirectory (no-one wants
lots of headers ending up in top-level /usr/include/) and your
headers must be able to include themselves with such a setup.
└── prj
├── inclu...
What is the difference between server side cookie and client side cookie?
...rence between creating cookies on the server and on the client? Are these called server side cookies and client side cookies? Is there a way to create cookies that can only be read on the server or on the client?
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What is the __del__ method, How to call it?
...is used, probably not like that: obj1.del() . So, my questions is how to call the __del__ method?
5 Answers
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How to select a single field for all documents in a MongoDB collection?
... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example ...