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Creating and Using DataTables 

A DataSet is made up of a collection of tables, relationships, and constraints. In ADO.NET, DataTable objects are used to represent the tables in a DataSet. A DataTable represents one table of in-memory relational data; the data is local to the .NET-based application in which it resides, but can be populated from a data source such as Microsoft SQL Server using a DataAdapter For more information, see Populating a DataSet from a DataAdapter.

The DataTable class is a member of the System.Data namespace within the .NET Framework class library. You can create and use a DataTable independently or as a member of a DataSet, and DataTable objects can also be used in conjunction with other .NET Framework objects, including the DataView. You access the collection of tables in a DataSet through the Tables property of the DataSet object.

The schema, or structure of a table is represented by columns and constraints. You define the schema of a DataTable using DataColumn objects as well as ForeignKeyConstraint and UniqueConstraint objects. The columns in a table can map to columns in a data source, contain calculated values from expressions, automatically increment their values, or contain primary key values.

In addition to a schema, a DataTable must also have rows to contain and order data. The DataRow class represents the actual data contained in a table. You use the DataRow and its properties and methods to retrieve, evaluate, and manipulate the data in a table. As you access and change the data within a row, the DataRow object maintains both its current and original state.

You can create parent-child relationships between tables using one or more related columns in the tables. You create a relationship between DataTable objects using a DataRelation. DataRelation objects can then be used to return the related child or parent rows of a particular row. For more information, see Adding a Relationship Between Tables.

In This Section

  • Manipulating Data in a DataTable
    Explains how to add, modify, and delete data in a table. Explains how to use DataTable events to examine changes to data in the table.
  • ADO.NET
    Describes the ADO.NET architecture and components, and how to use them to access existing data sources and manage application data.
  • Using DataSets in ADO.NET
    Provides information about the ADO.NET DataSet including how to create relationships between tables.
  • DataSet Class
    Provides reference information about the DataSet object.
  • DataTable Class
    Provides reference information about the DataTable object.