Batching SQL Statements - Return Long Raw

Question

I have been using the .NET Framework Data Provider for Oracle and have run into the following limitation.
I need to batch several SQL statements at one time and return a datareader (or another object) with those values. The .NET Framework Data Provider for Oracle from Microsoft doesn't support batching up SQL statements in this manner. Additionally, the values I need to return include a LONGRAW field. From the research I've done PL-SQL can only return 32KB of data for a LONGRAW field if we were to try a different approach like using a stored procedure and a REF CURSOR.
My questions are:
1.) Will the ODP support batched SQL statements? For example, can I issue the following SQL statements and get a datareader?
Select field1, field2 from table1;
Select feild1, field2 from table2;
Select feild1, field2 from table3;
2.) Is there the 32 KB limitation on LONGRAW fields and PL-SQL in Oracle 8.1.7.2.0?
3.) Any suggestions?

Answer 1

1. With ODP.NET, you can batch your SQL statements using anonymous PL/SQL block. For example,
begin
open :1 for select * from emp;
open :2 for select * from dept;
open :3 for select col1 from test;
end;
You need to create three parameters with type OracleDbType.RefCursor and bind them as Output parameters. If you execute the above statement using OracleCommand's ExecuteNonQuery method, you would get three REF Cursors in the Value property of OracleParameter object. You can create an OracleDataReader or populate the Data Set using any or all of these REF Cursors in any order. If you execute the above statement using OracleCommand's ExecuteReader method, you would get OracleDataReader for the first REF Cursor and you would be able to get the OracleDataReader for other REF Cursors using OracleDataReader's NextResult method. Note that ODP.NET does not impose a limitation of closing the first OracleDataReader before opening the second one.
2. Long/Long Raw 32K limitation is imposed by PL/SQL and one way to bypass that limitation is to use LOBs instead. Having LOBs in the stored procedure or anonymous PL/SQL blocks allow you to access data upto 4GB.