Dataset VS. DataReader


The DataSet class in ADO.NET operates in a fully disconnected manner, allowing for an independent representation of a collection of database objects, encompassing related tables, constraints, and relationships. This powerful class provides a consistent relational programming model, accommodating multiple data sources from various domains. Functioning as a compact database within the application's memory area, the DataSet stores both the schema and data, enabling efficient data manipulation. With the DataSet, you can select data from tables, create views based on tables, and navigate child rows through relationships. Additionally, the DataSet offers rich features like XML serialization for data storage and retrieval.


On the other hand, the DataReader serves the purpose of retrieving a read-only, forward-only stream of data from data sources. Designed with a connection-oriented nature, the DataReader requires an active connection to fetch data from the database. It excels in scenarios where read-only access is sufficient and random access is not required. By retrieving one row at a time, the DataReader minimizes network overhead, offering efficient data retrieval. The query results are streamed back to the client and stored in the network buffer until requested using the Read method. It's important to note that the DataReader is read-only and doesn't support transactional operations. It is particularly useful when displaying data to users that doesn't require transactional capabilities.


It is worth mentioning that the DataSet does have certain drawbacks, such as its relatively slower speed due to resource consumption. The overhead is primarily attributed to the inclusion of related tables, constraints, and relationships within the DataSet. However, when there is a need for forward-only access to query results, the DataReader proves to be the optimal choice, as it offers the fastest retrieval mechanism in such scenarios.