dotConnect for PostgreSQL Documentation
Devart.Common Namespace / DbDataTable Class / QueryRecordCount Property
Example

QueryRecordCount Property
Determines whether DbDataTable should perfrom additional request to determine quantity of records in the result set.
Syntax
'Declaration
 
Public Property QueryRecordCount As Boolean
 

Property Value

If true, an additional request to server is executed, and the RecordCount is updated.
Remarks
The SQL statement for obtaining the record count is generated basing on the SelectCommand object. This property can be used when FetchAll is false, otherwise it is useless.
Example
The following example demonstrates how to use the QueryRecordCount property.
static void UseDataTable(DbDataTable myDataTable, DbConnection myConnection) {

  myDataTable.Connection = myConnection;
  myDataTable.SelectCommand = myConnection.CreateCommand();
  myDataTable.SelectCommand.CommandText = "SELECT * FROM Test.Dept";

  myDataTable.QueryRecordCount = false;
  myDataTable.Active = true;
  int count = myDataTable.RecordCount; //the number of currently fetched rows
  myDataTable.Active = false;

  myDataTable.QueryRecordCount = true;
  myDataTable.Active = true;
  count = myDataTable.RecordCount; //the real number of rows in the table
  myDataTable.Active = false;
}
Private Shared Sub UseDataTable5(ByVal myDataTable As DbDataTable, ByVal myConnection As DbConnection)
  myDataTable.Connection = myConnection
  myDataTable.SelectCommand = myConnection.CreateCommand
  myDataTable.SelectCommand.CommandText = "SELECT * FROM Test.Dept"
  myDataTable.QueryRecordCount = False

  myDataTable.Active = True
  Dim num1 As Integer = myDataTable.RecordCount 'the number of currently fetched rows

  myDataTable.Active = False
  myDataTable.QueryRecordCount = True

  myDataTable.Active = True
  num1 = myDataTable.RecordCount 'the real number of rows in the table

  myDataTable.Active = False
End Sub
Requirements

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

See Also