Relationships in Datasets

A dataset can contain related tables like a relational database. The object that facilitates a relationship between data tables is a DataRelation object. The following topics provide information about ADO.NET DataRelation objects, how to create them, and how to use them to work with data in related tables.

Note

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In This Section

• Introduction to DataRelation Objects
  Provides an overview of how datasets allow you to specify relationships between tables and how you can take advantage of these relationships.

• How to: Create DataRelations with the Dataset Designer
  Explains how to use the Dataset Designer to add a DataRelation object to a dataset.

• How to: Access Records in Related DataTables
  Explains how to programmatically return related records in a typed dataset with tables in a one-to-many relationship.

• How to: Display or Hide Relationship Names on the Dataset Designer
  Explains how to toggle on and off the displaying of the relationship name on the Dataset Designer surface.

• Walkthrough: Creating a Relationship between Data Tables
  Provides step-by-step instructions for creating two data tables with the Dataset Designer and adding a relation between them.

Reference

• DataRelation
  Represents a parent/child relationship between two T:System.Data.DataTable objects.

• GetChildRows
  Gets the child rows of a T:System.Data.DataRow.

• GetParentRow
  Gets the parent rows of a T:System.Data.DataRow.

• Rule
  Indicates the action that occurs when a ForeignKeyConstraint is enforced.

• Unique
  Gets or sets a value indicating whether the values in each row of the column must be unique.

• Constraint
  Represents a constraint that can be enforced on one or more DataColumn objects.

Related Sections

• Adding DataRelations (ADO.NET)
  Describes how to create relations between tables in a DataSet.

• Navigating DataRelations (ADO.NET)
  Describes how to use the relations between tables in a DataSet to return the child or parent rows of a parent-child relationship.

• Nesting DataRelations (ADO.NET)
  Discusses the importance of nested DataRelation objects when representing the contents of a DataSet as XML data, and describes how to create them.