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UniqueConstraint.IsPrimaryKey Property

  • Reference

Definition

Namespace:
System.Data
Assembly:
System.Data.Common.dll
Assembly:
System.Data.dll
Assembly:
netstandard.dll
Source:
UniqueConstraint.cs
Source:
UniqueConstraint.cs
Source:
UniqueConstraint.cs

Gets a value indicating whether or not the constraint is on a primary key.

public:
 property bool IsPrimaryKey { bool get(); };
public bool IsPrimaryKey { get; }
[System.Data.DataSysDescription("KeyConstraintIsPrimaryKeyDescr")]
public bool IsPrimaryKey { get; }
member this.IsPrimaryKey : bool
[<System.Data.DataSysDescription("KeyConstraintIsPrimaryKeyDescr")>]
member this.IsPrimaryKey : bool
Public ReadOnly Property IsPrimaryKey As Boolean

Property Value

Boolean

true, if the constraint is on a primary key; otherwise, false.

Attributes
DataSysDescriptionAttribute

Examples

The following example checks the IsPrimaryKey property.

Private Sub GetPrimaryKey()
    Dim dataRelation As DataRelation
    Dim uniqueConstraint As UniqueConstraint

    ' Get a DataRelation from a DataSet.
    dataRelation = DataSet1.Relations("CustomerOrders")

    ' Get the ParentKeyConstraint.
    uniqueConstraint = dataRelation.ParentKeyConstraint

    ' Test if the IsPrimaryKey is true.
    If uniqueConstraint.IsPrimaryKey Then
       Console.WriteLine("IsPrimaryKey=True")
    Else
       Console.WriteLine("IsPrimaryKey=False")
    End If
 End Sub

Remarks

A table usually includes a primary key that ensures every row is unique. In some tables, the primary key may be made up of more than one column. For example, a primary key for a table containing names might be made up of both the first and last names as well. To create a primary key with more than one column, set the Columns property to an array of DataColumn objects.

Applies to

See also