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A beginner's guide to SQL database design [closed]
...n:
Keep different types of data separate - don't store addresses in your order table, link to an address in a separate addresses table, for example.
I personally like having an integer or long surrogate key on each table (that holds data, not those that link different tables together, e,g., m:n re...
How to schedule a function to run every hour on Flask?
...om apscheduler.schedulers.background import BackgroundScheduler
def print_date_time():
print(time.strftime("%A, %d. %B %Y %I:%M:%S %p"))
scheduler = BackgroundScheduler()
scheduler.add_job(func=print_date_time, trigger="interval", seconds=3)
scheduler.start()
# Shut down the scheduler when ...
Importing modules from parent folder
...cit, the procedure is to import sys and then sys.path.append("..\<parent_folder>")
– BCJuan
Nov 20 '19 at 16:12
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Comma in C/C++ macro
...ose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which prevents it being read as a type in most contexts.
A nice trick to workaround this is that in C++, you can extract a typ...
How do I use raw_input in Python 3
I am using Python 3.1 and can't get the raw_input to "freeze" the dos pop-up. The book I'm reading is for Python 2.5 and I'm using Python 3.1
...
Is there a difference between “==” and “is”?
... most cases this logic is true, but it relies on the implementation of the __eq__ special method. As the docs say,
The default behavior for equality comparison (== and !=) is based on
the identity of the objects. Hence, equality comparison of instances
with the same identity results in equa...
How can I create a Makefile for C projects with SRC, OBJ, and BIN subdirectories?
...$@ $(LFLAGS) $(OBJECTS)
@echo "Linking complete!"
Once that's all in order, you might consider more sophisticated dependency handling; if you modify one of the header files, this makefile will not know which objects/executables must be rebuilt. But that can wait for another day.
EDIT:
Sorry, ...
rails i18n - translating text with links inside
...
en.yml
log_in_message_html: "This is a text, with a %{href} inside."
log_in_href: "link"
login.html.erb
<p> <%= t("log_in_message_html", href: link_to(t("log_in_href"), login_path)) %> </p>
...
Does C have a “foreach” loop construct?
...ave a foreach, but macros are frequently used to emulate that:
#define for_each_item(item, list) \
for(T * item = list->head; item != NULL; item = item->next)
And can be used like
for_each_item(i, processes) {
i->wakeup();
}
Iteration over an array is also possible:
#define f...
`staticmethod` and `abc.abstractmethod`: Will it blend?
...
class abstractstatic(staticmethod):
__slots__ = ()
def __init__(self, function):
super(abstractstatic, self).__init__(function)
function.__isabstractmethod__ = True
__isabstractmethod__ = True
class A(object):
__metaclass__ = abc.AB...