Sessions

The IConfiguration and ISession interfaces are the main entry points for Dashing. As mentioned your IConfiguration essentially details how your domain model is mapped (and you usually have just one of these) while your ISession is a lightweight object that you use to actually perform queries.

There are pretty much two methods available for getting an ISession, both of which are defined on the IConfiguration interface. They are BeginSession and BeginTransactionLessSession. BeginSession will generally wrap your connection in an IDbTransaction so that you can commit/rollback your work as you wish while BeginTransactionLessSession will simply open a connection to the database without a transaction.

BeginSession

If you use the parameterless BeginSession function Dashing will manage your connection and transaction for you - this means that when you make your first query on an ISession returned by BeginSession() Dashing will open a new IDbConnection and begin a new IDbTransaction. All subsequent queries on that session will use them. In order to commit your transaction you must call Complete() on the ISession, otherwise your transaction will be rolled back when it is disposed of (ISession implements IDisposable.)

In addition to the parameterless function there are two more overloads which allow you to provide the IDbConnection or IDbTransaction yourself so that you can then manage their lifetime explicitly.

An example of opening a session is:

IConfiguration config = ...;
using (var session = config.BeginSession()) {
	var post = await session.GetAsync<Post>(1);
	session.Complete();
}

Note that if you're developing a web application and are using an Inversion of Control container we'd suggest setting up your IConfiguration with a Singleton lifestyle and your ISession's with a lifestyle that equates to one per web request.

BeginTransactionLessSession

This function is similar to the above but does not use an IDbTransaction. As a result, most databases will automatically commit any changes for you. We would suggest that you stick with the BeginSession() method unless you particularly don't need an IDbTransaction. This can be useful if, for example, you are using a read only type database as it does result in a performance increase.

As with BeginSession it has an overload that allows you to pass in your own IDbConnection.