Data room Charging System (Personal Edition)-selection of entities and tables

The previous article introduced some of ADO. Net's knowledge. This article will summarize the table transfer or object transfer used in the system.

The usage of sqlhelper is involved in the data center charging system. It is difficult for functions in the helper class to return entities or return tables. Below is a summary of them:

	Datatable	Dataset	Entity	Entity set
Definition	Datatable is a data grid control, or can be understood as a virtual table.	Dataset objects are the representation of data in memory. It includes multiple able objects, and datatable contains columns and rows, just like a table in a common database.	A data object, which can be used to differentiate objective things.	A set of entities of the same class
Applicability	Convenient and flexible operations on small data		The development of large projects is reliable, secure, and easy to maintain.

Here, transferring objects between layers is more secure. For some large projects, this must be considered. However, the workload of creating each entity cannot be underestimated; microsoft provides you with original data access such as datatable and dataset, facilitating your use.

The above is your understanding of them. You are welcome to correct your criticism!