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PostgreSQL: Which Datatype should be used for Currency?
... have to deal with multiple currencies you'll need that much precision for converting. No matter what I'm presenting a user, I always store to US Dollar. In that way I can readily convert to any other currency, given the conversion rate for the day involved.
If you never do anything but one curre...
Inline functions vs Preprocessor macros
...ts.
Inline functions are actual functions whose body is directly injected into their call site. They can only be used where a function call is appropriate.
Now, as far as using macros vs. inline functions in a function-like context, be advised that:
Macros are not type safe, and can be expanded ...
How to delete duplicate rows in SQL Server?
...icated.
SELECT DISTINCT [col1],[col2],[col3],[col4],[col5],[col6],[col7]
INTO [newTable]
Go into the object explorer and delete the old table.
Rename the new table with the old table's name.
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How can I represent an 'Enum' in Python?
...TWO')
>>> Numbers.ZERO
0
>>> Numbers.ONE
1
Support for converting the values back to names can be added this way:
def enum(*sequential, **named):
enums = dict(zip(sequential, range(len(sequential))), **named)
reverse = dict((value, key) for key, value in enums.iteritems(...
How Should I Declare Foreign Key Relationships Using Code First Entity Framework (4.1) in MVC3?
...for resources on how to declare foreign key relationships and other constraints using code first EF 4.1 without much luck. Basically I am building the data model in code and using MVC3 to query that model. Everything works via MVC which is great (kudos to Microsoft!) but now I want it NOT to work be...
How to use WinForms progress bar?
...port progress back to the UI thread.
For example:
private void Calculate(int i)
{
double pow = Math.Pow(i, i);
}
private void button1_Click(object sender, EventArgs e)
{
progressBar1.Maximum = 100;
progressBar1.Step = 1;
progressBar1.Value = 0;
backgroundWorker.RunWorkerAsync(...
Advantage of switch over if-else statement
...n, so you don't lose anything. If in doubt put the most common cases first into the switch statement.
In the best case the optimizer may find a better way to generate the code. Common things a compiler does is to build a binary decision tree (saves compares and jumps in the average case) or simply ...
Check whether a path is valid in Python without creating a file at the path's target
...file name).
I need to test if the file-name is a valid, e.g. if the file-system will allow me to create a file with such a name.
The file-name has some unicode characters in it.
...
C++ templates that accept only certain types
...<typename T> class my_template; // Declare, but don't define
// int is a valid type
template<> class my_template<int> {
...
};
// All pointer types are valid
template<typename T> class my_template<T*> {
...
};
// All other types are invalid, and will caus...
Assign null to a SqlParameter
The following code gives an error - "No implicit conversion from DBnull to int."
18 Answers
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