The ParentDataRelation class is designed to establish a master-detail relationship where details data is not cached on the client. Every time the current position in the master table is changed, the client DbDataTable requests the appropriate portion of data from the server.
Use property ParentTable to specify master DbDataTable, and the properties ParentColumnNames and ChildColumnNames to describe the relationiship.
Note that this feature can be used only for two instances of DbDataTable class that have same DbDataTable.Owner. In other words, the DbDataTable objects must reside on the same forms.
PgSqlConnection connection = new PgSqlConnection( "host=server;database=test;user id=postgres;"); connection.Open(); PgSqlDataTable deptTable = new PgSqlDataTable("SELECT * FROM dept", connection); PgSqlDataTable empTable = new PgSqlDataTable("SELECT * FROM emp", connection); empTable.ParentRelation.ParentTable = deptTable; empTable.ParentRelation.ParentColumnNames = new string[] { "deptno" }; empTable.ParentRelation.ChildColumnNames = new string[] { "deptno" }; deptTable.Owner = this; empTable.Owner = this; deptTable.FetchAll = true; empTable.FetchAll = true; deptTable.Open(); empTable.Open(); deptDataGrid.DataSource = deptTable; empDataGrid.DataSource = empTable;
Dim connection As New PgSqlConnection( _ "host=server;database=test;user id=postgres;") connection.Open() Dim deptTable As New PgSqlDataTable("SELECT * FROM dept", connection) Dim empTable As New PgSqlDataTable("SELECT * FROM emp", connection) empTable.ParentRelation.ParentTable = deptTable empTable.ParentRelation.ParentColumnNames = New String() {"deptno"} empTable.ParentRelation.ChildColumnNames = New String() {"deptno"} deptTable.Owner = Me empTable.Owner = Me deptTable.FetchAll = True empTable.FetchAll = True deptTable.Open() empTable.Open() deptDataGrid.DataSource = deptTable empDataGrid.DataSource = empTable
System.Object
Devart.Common.ParentDataRelation
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2