to hack the sparql2sql thing for quicker fulltext search, the right class to understand what happens is:

com.hp.hpl.jena.query.sql.engine.RDBQueryEngine;

there, set a breakpoint into getPlanForQueryPattern/QueryIterator exec()

of, fine idea:

SELECT CONVERT(j.subj, CHAR) as Subj, CONVERT(j.Prop, CHAR) as Prop, CONVERT(j.Obj, CHAR) as Obj FROM jena_g1t1_stmt j WHERE LOWER(CONVERT(j.Obj, CHAR)) LIKE "%leo%" AND j.Prop = "Uv::​http://www.w3.org/2000/01/rdf-schema#label"