@Override public Set<Integer> visit(SelectAllDatabaseQuery databaseQuery, Boolean forUpdate) { SelectJoinStep<Record1<Integer>> select = dsl.select(DSL.field("did", Integer.class)) .from(DSL.tableByName(colSchema.getName(), "root")); Result<Record1<Integer>> fetched; if (forUpdate) { fetched = select.forUpdate().fetch(); } else { fetched = select.fetch(); } Set<Integer> result = Sets.newHashSetWithExpectedSize(fetched.size()); for (Record1<Integer> record1 : fetched) { result.add(record1.value1()); } return result; } }