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Devart.Data.PostgreSql Namespace / PgSqlCursor Class / GetDataReader Method / GetDataReader() Method
Example

In This Topic
    GetDataReader() Method
    In This Topic
    Gets an PgSqlDataReader for the specified cursor.
    Syntax
    'Declaration
     
    Public Overloads Function GetDataReader() As PgSqlDataReader
    public PgSqlDataReader GetDataReader()

    Return Value

    The PgSqlDataReader for the cursor.
    Remarks
    An PgSqlDataReader allows you to read data from the cursor at the server.
    Example
    This example demonstrates usage of PgSqlCursor class. To execute this code you have to create the following function on the server:
    CREATE OR REPLACE FUNCTION refcursorfunc(OUT p refcursor) AS
    $BODY$ 
    DECLARE 
    v_refcursor refcursor; 
    BEGIN 
    OPEN v_refcursor FOR SELECT deptno FROM dept; 
    p := v_refcursor;
    END; 
    $BODY$
      LANGUAGE 'plpgsql' VOLATILE;
    
    PgSqlCommand cmd = new PgSqlCommand("refcursorfunc");
    cmd.Connection = myConnection;
    cmd.CommandType = CommandType.StoredProcedure;
    cmd.ParameterCheck = true;
    myConnection.Open();
    PgSqlTransaction t = myConnection.BeginTransaction();
    try {
      cmd.ExecuteNonQuery();
    PgSqlCursor cursor = cmd.Parameters["p"].PgSqlValue as PgSqlCursor;
      using (PgSqlDataReader rd = cursor.GetDataReader()) {
        while (rd.Read())
          Console.WriteLine(rd.GetValue(0));
      }
    }
    finally {
      t.Commit();
      myConnection.Close();
    }
    Dim cmd As New PgSqlCommand("refcursorfunc")
    cmd.Connection = (Me.myConnection)
    cmd.CommandType = CommandType.StoredProcedure
    cmd.ParameterCheck = True
    Me.myConnection.Open()
    Dim t As PgSqlTransaction = Me.myConnection.BeginTransaction
    Try
        cmd.ExecuteNonQuery()
    Dim cursor As PgSqlCursor = TryCast(cmd.Parameters("p").PgSqlValue, PgSqlCursor)
    Using rd As PgSqlDataReader = cursor.GetDataReader
            Do While rd.Read
                Console.WriteLine(rd.GetValue(0))
            Loop
        End Using
    Finally
        t.Commit()
        Me.myConnection.Close()
    End Try
    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