To search for title (or other) words in katkat.katkat's source field or in some other sort of bibliographic query, use the gavo_hasword locally defined function. This basically works a bit like you'd expect from search engines: case-insensitive, and oblivious to any context.
Try the following query:
select *
from katkat.katkat
where gavo_hasword('variable', source)
and minEpoch<1900
This query selects reflected observations and their epochs and equinoxes from the identified objects within arigfh.id. This example in particular shows how to decode combined flags (i.e., flags-like numbers in which digits (or groups of digits) need to be extracted to allow interpretation.
Try the following query:
SELECT decCat, raj2000, dej2000, epDec, eqDec
FROM arigfh.id
WHERE 4=mod(decflags/10000, 10)