I am trying to issue the SET PDQPRIORITY command and SET ISOLATION within a query that's going through ODBC to an Informix 9.21 engine. I am wondering if this is possible. For instance, in dbaccess, I would enter the following:

set pdqpriority 50;
set isolation dirty read;
select * from my_table

When I enter the same, say from WinSQL via ODBC, I get the following error:

ODBC Error: [Informix][Informix ODBC Driver][Informix]Cannot use a select or any of the database statements in a multi-query prepare.

Is there a way to use the SET statement with ODBC?

I know optimizer directives can be passed by enclosing in {}, but that doesn't appear to work with SET. When I put the braces around the SET statements, the query runs but the SETs are ignored.