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Devart.Data.PostgreSql Namespace / PgSqlCommand Class / FetchAll Property
Example

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    FetchAll Property (PgSqlCommand)
    In This Topic
    Gets or sets a value indicating whether the PgSqlDataReader object will request data from the server on execution ExecuteReader method.
    Syntax
    'Declaration
     
    Public Property FetchAll As Boolean
    public bool FetchAll {get; set;}

    Property Value

    true, if the PgSqlDataReader object will request data from the server on execution ExecuteReader; otherwise false. The default value is true.
    Remarks
    FetchAll property allows your application to reduce greatly size of used memory on processing big volume data. If set to true, memory will be allocated for all data returned by your SELECT. If FetchAll property is set to false, memory will be allocated only at most for hundred records and on retrieving next records previous rows will be rewritten.
    Example
    The following example fills two ListBox by data from the PgSqlDataReader. This sample demonstrates ability to navigate through the PgSqlDataReader several times when FetchAll property set to true.
    public void FillListBox()
    {
      PgSqlCommand cmd;
      PgSqlDataReader reader;
      ListBox deptnoList, nameList;
      cmd = new PgSqlCommand("select deptno, dname from dept");
      cmd.FetchAll = true;
      reader = cmd.ExecuteReader();
      foreach (IDataRecord rec in reader) {
        deptnoList.Items.Add(rec["deptno"]);
      }
      foreach (IDataRecord rec in reader) {
        nameList.Items.Add(rec["dname"]);
      }
    }
    Public Sub FillListBox()
      Dim cmd As PgSqlCommand
      Dim reader As PgSqlDataReader
      Dim deptnoList As ListBox
      Dim nameList As ListBox
      cmd = New PgSqlCommand("select deptno, dname from dept")
      cmd.FetchAll = True
      reader = cmd.ExecuteReader()
      Dim rec As IDataRecord
      For Each rec In reader
        deptnoList.Items.Add(rec("deptno"))
      Next
      For Each rec In reader
        nameList.Items.Add(rec("dname"))
      Next
    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