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MySQL Removing Some Foreign keys
...You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY'
– Gayan Dasanayake
Aug 26 '17 at 2:48
...
Pandas percentage of total with groupby
...you can calculate the percentage in a simpler way -- just groupby the state_office and divide the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
...
C++ display stack trace on exception
...
On the home page of StackTrace, I see throw stack_runtime_error. Am I correct in deducing that this lib only works for exceptions derived from that class, and not for std::exception or exceptions from third-party libraries?
– Thomas
No...
Are duplicate keys allowed in the definition of binary search trees?
...about them. As just a starter, take a look here: en.wikipedia.org/wiki/List_of_data_structures#Trees
– Andrew
Sep 16 at 0:52
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ASP.NET Web API - PUT & DELETE Verbs Not Allowed - IIS 8
...lines from applicationhost.config.
<add name="WebDAVModule" image="%IIS_BIN%\webdav.dll" />
<add name="WebDAVModule" />
<add name="WebDAV" path="*" verb="PROPFIND,PROPPATCH,MKCOL,PUT,COPY,DELETE,MOVE,LOCK,UNLOCK" modules="WebDAVModule" resourceType="Unspecified" requireAccess="None"...
What new capabilities do user-defined literals add to C++?
...its>
inline constexpr std::bitset<sizeof...(Bits)>
operator"" _bits() noexcept
{
static_assert(checkbits<Bits...>::valid, "invalid digit in binary string");
return std::bitset<sizeof...(Bits)>((char []){Bits..., '\0'});
}
int
main()
{
auto bits = 0101010101010...
What are the GCC default include directories?
...,-v -x c++ - -fsyntax-only
ignoring nonexistent directory "/usr/lib/gcc/x86_64-redhat-linux/4.8.2/include-fixed"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-redhat-linux/4.8.2/../../../../x86_64-redhat-linux/include"
#include "..." search starts here:
#include <...> search starts here:...
How to redirect to a 404 in Rails?
...tionality built in already. If you want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveReco...
How to get POSTed JSON in Flask?
...of all, the .json attribute is a property that delegates to the request.get_json() method, which documents why you see None here.
You need to set the request content type to application/json for the .json property and .get_json() method (with no arguments) to work as either will produce None other...
Django admin: how to sort by one of the custom list_display fields that has no database field
How could I sort Customers, depending on number_of_orders they have?
3 Answers
3
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