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C# Entity-Framework: How can I combine a .Find and .Include on a Model Object?
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I would really recommend using the latter (SingleOrDefault), ToList will retrieve all entries first and then select one
– Sander Rijken
Sep 8 '11 at 13:51
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Efficient SQL test query or validation query that will work across all (or most) databases
...for idleness. For example, the JDBC pooling library c3p0 has a property called preferredTestQuery , which gets executed on the connection at configured intervals. Similarly, Apache Commons DBCP has validationQuery .
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django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb
...ysql-python
When I did the above, I got the error "EnvironmentError: mysql_config not found"
To fix this, I did the below in terminal:
export PATH=$PATH:/usr/local/mysql/bin
When I reran step 1, I get a new error "error: command 'cc' failed with exit status 1"
To fix this, I did the...
How to open files relative to home directory
...a mere convention; indeed, if you look at the documentation for File.expand_path, it correctly interprets the tilde, but it's a feature of the function itself, not something inherent to the underlying system; also, File.expand_path requires the $HOME environment variable to be correctly set. Which b...
Calculating Distance between two Latitude and Longitude GeoCoordinates
...tic UnitOfLength Miles = new UnitOfLength(1);
private readonly double _fromMilesFactor;
private UnitOfLength(double fromMilesFactor)
{
_fromMilesFactor = fromMilesFactor;
}
public double ConvertFromMiles(double input)
{
return input*_fromMilesFactor;
}
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How to generate all permutations of a list?
How do you generate all the permutations of a list in Python, independently of the type of elements in that list?
33 Answer...
Why am I getting an Exception with the message “Invalid setup on a non-virtual (overridable in VB) m
...ethods and sealed classes. While running a test using mock object, MOQ actually creates an in-memory proxy type which inherits from your "XmlCupboardAccess" and overrides the behaviors that you have set up in the "SetUp" method. And as you know in C#, you can override something only if it is marked ...
How to access the correct `this` inside a callback?
...d inside each function and its value only depends on how the function was called, not how/when/where it was defined. It is not affected by lexical scopes like other variables (except for arrow functions, see below). Here are some examples:
function foo() {
console.log(this);
}
// normal functio...
PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
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