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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...
convert an enum to another type of enum
...then cast it to the other enum (considering that you want the mapping done based on value):
Gender2 gender2 = (Gender2)((int)gender1);
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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...
Find a file in python
...leAttributesW(unicode(path)) & FILE_ATTRIBUTE_REPARSE_POINT)
def find(base, filenames):
hits = []
def find_in_dir_subdir(direc):
content = scandir(direc)
for entry in content:
if entry.name in filenames:
hits.append(os.path.join(direc, entry....
PHPExcel auto size column width
...column is set to AutoSize, PHPExcel attempts to calculate the column width based on the calculated value of the column (so on the result of any formulae), and any additional characters added by format masks such as thousand separators.
By default, this is an estimated width: a more accurate calcul...
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...
Does my application “contain encryption”?
...ermine that your app is not classified under Category 5, Part 2 of the EAR based on the guidance provided by BIS at encryption question. The Statement of Understanding for medical equipment in Supplement No. 3 to Part 774 of the EAR can be accessed at Electronic Code of Federal Regulations site. Ple...
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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