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What's the difference between belongs_to and has_one?
...
It's about where the foreign key sits.
class Foo < AR:Base
end
If foo belongs_to :bar, then the foos table has a bar_id column
If foo has_one :bar, then the bars table has a foo_id column
On the conceptual level, if your class A has a has_one relationship with class B then ...
Naming convention - underscore in C++ and C# variables
...ou will see all that happens in the background. Here is a snippet:
ios_base::iostate __err = ios_base::iostate(ios_base::goodbit);
try
{
__streambuf_type* __sb = this->rdbuf();
if (__sb)
{
if (__sb->pubsync() == -1)
__err |= ios_base::badbit;
else
...
sqlalchemy: how to join several tables by one query?
...e to setup integer primary keys for everything, but whatever):
class User(Base):
__tablename__ = 'users'
email = Column(String, primary_key=True)
name = Column(String)
class Document(Base):
__tablename__ = "documents"
name = Column(String, primary_key=True)
author_email = C...
Caveats of select/poll vs. epoll reactors in Twisted
Everything I've read and experienced ( Tornado based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
...
Real life trading API [closed]
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TradeStation also has an HTTP based api, check out the docs at: tradestation.github.io/webapi-docs
– dk.
Jan 5 '14 at 21:40
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For every character in string
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Looping through the characters of a std::string, using a range-based for loop (it's from C++11, already supported in recent releases of GCC, clang, and the VC11 beta):
std::string str = ???;
for(char& c : str) {
do_things_with(c);
}
Looping through the characters of a std::stri...
The type or namespace name 'Objects' does not exist in the namespace 'System.Data'
...ng entities, C# and SQL Server to create an n-tier app. I am creating some base classes common to all my DAL components. In this base class, i want to handle the connection state of the ObjectContext base class inherited by entities object.
...
How can I implement an Access Control List in my Web MVC application?
...lot of classes. Large part of the classes can be separated in two groups , based on the responsibility:
- Domain Business Logic
(read more: here and here):
Instances from this group of classes deal with computation of values, check for different conditions, implement sales rules and do all the r...
What is getattr() exactly and how do I use it?
...me, getattr is easiest to explain this way:
It allows you to call methods based on the contents of a string instead of typing the method name.
For example, you cannot do this:
obj = MyObject()
for x in ['foo', 'bar']:
obj.x()
because x is not of the type builtin, but str. However, you CAN d...
How to make code wait while calling asynchronous calls like Ajax [duplicate]
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Use callbacks. Something like this should work based on your sample code.
function someFunc() {
callAjaxfunc(function() {
console.log('Pass2');
});
}
function callAjaxfunc(callback) {
//All ajax calls called here
onAjaxSuccess: function() {
callbac...