GetDataReader() Method

In This Topic

Gets an PgSqlDataReader for the specified cursor.

Syntax

Visual Basic
C#

'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;

csharp

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();
}

Visual Basic

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

Reference

PgSqlCursor Class
PgSqlCursor Members
Overload List

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