SQL syntax - using the same table twice in FROM statement

Twisted data structures - I'm not even sure how to ask this question. Conditions: INFORMIX-OnLine Version 7.23.UC11 INFORMIX-SQL Version 7.20.UD1 I can join between two tables just fine. I can do a simulated join between a table and itself just fine. I don't want to, though. Is there an easier way? Example syntax I'm using now: select a.f1, a.f2, b.f5, b.f6 from table1 a, table1 b where a.f1 = "X" and a.f1 = b.f5 The goal here is to get a dataset out of the table, then go back and get related data that really should be in a separate table, but is kept in the same table using the same fields. NOTE: In the actual data structure, there are several types of data images kept here, and only the fields needed for a particular type image are used leaving lots of blank space in the record. I can't split the data appropriately into multiple tables (customer need). I don't want to build two different views of the same table (excessive overhead?). I would LIKE to have a more efficient way since I'll go into production mode with tables in the 20-40 million range rather than the <10K range. Any ideas? Thanks.... Rob