Help Desk Ticket Reference: https://c.na7.visual.force.com/apex/Case_View?id=500A0000008RaPH
Workaround Description: You can use LIKE 'select nspname from pg_catalog.pg_namespace where nspname LIKE 'LOOKHERE%'

project_key: SOA

The attached testing vdb contains the following namespaces:
LOOKHERE                                                                                                                                                   TestPG                                                                                                                                                      LOOKAGAIN 

If you run the following query via ODBC (JDBC works ):
select nspname from pg_catalog.pg_namespace where nspname = 'LOOKHERE'

It returns zero rows, but if you run the same query with 'LOOKAGAIN' in your criteria you get the one row,  It seems that any namespace ending in an E doesn't match via ODBC.