There is no direct support for a fixed byte type, nor is our blobtype comparable, and we don't have a binary literal escape syntax. That said, there are a couple of things you could do. Assuming that you can retrieve the byte value using getBytes, then you can model the column type as blob. To make it comparable you would have to convert to string:
select * from s1 where toChars(s1.f1, 'ISO-8859-1') = 'target bytes encoded in ISO-8859-1'
The choice of charset just needs to be something where each character is represented by a single byte and each byte will map to a character value. This would allow for comparisons to be performed in Teiid. However pushdown would be an issue.
To go further and support pushdown, you would either need to stay with the blob type add support for the toChars function (which depending on your usage of charsets may not be possible), or model the column as string and customize the translator to properly convert literal bind values etc. when the native type is CHAR FOR BIT DATA.
It seems like we probably need an enhancement here to introduce handling for binary strings. Even if it's as simple as modeling the source coulmn type as string and having an extension metadata property for the charset.
Thanks Steve for feedback, we deal with EBCDIC and binary content, so the some sort of hex string enhancement would be really nice to have in future.
+1, log a feature request at https://issues.jboss.org/browse/TEIID
Support would be good step toward integrating the legacy systems. Curious, how are intending currently to handle the conversion, are you writing a custom translator for this?