Querying with the DataReader
The CData ADO.NET Provider for Oracle Sales implements two ADO.NET interfaces you can use to retrieve data from Oracle Sales: OracleSalesCloudDataAdapter and OracleSalesCloudDataReader objects. Whereas OracleSalesCloudDataAdapter objects retrieve a single result set of all the data that matches a query, OracleSalesCloudDataReader objects fetch data in subset increments as needed.
Using the OracleSalesCloudDataReader
The OracleSalesCloudDataReader retrieves data faster than the OracleSalesCloudDataAdapter because it can retrieve data in pages. As you read data from the OracleSalesCloudDataReader, it periodically requests the next page of results from the data source, if required. This causes results to be returned at a faster rate. The following example selects all the columns from the Opportunities table:
C#
string connectionString = "HostURL=https://my.host.oraclecloud.com; Username=abc123; Password=abcdef;"; using (OracleSalesCloudConnection connection = new OracleSalesCloudConnection(connectionString)) { OracleSalesCloudCommand cmd = new OracleSalesCloudCommand("SELECT * FROM Opportunities", connection); OracleSalesCloudDataReader rdr = cmd.ExecuteReader(); while (rdr.Read()) { Console.WriteLine(String.Format("\t{0} --> \t\t{1}", rdr["OptyId"], rdr["Name"])); } }
VB.NET
Dim connectionString As String = "HostURL=https://my.host.oraclecloud.com; Username=abc123; Password=abcdef;" Using connection As New OracleSalesCloudConnection(connectionString) Dim cmd As New OracleSalesCloudCommand("SELECT * FROM Opportunities", connection) Dim rdr As OracleSalesCloudDataReader = cmd.ExecuteReader() While rdr.Read() Console.WriteLine([String].Format(vbTab & "{0} --> " & vbTab & vbTab & "{1}", rdr("OptyId"), rdr("Name"))) End While End Using