return me the total citations of papers in the VLDB conference before 2005 .
SELECT SUM ( t2.citation_num ) FROM publication AS t2 JOIN conference AS t1 ON t2.cid  =  t1.cid WHERE t1.name  =  "VLDB" AND t2.year  <  2005;
SELECT SUM ( t2.citation_num ) FROM publication AS t2 JOIN conference AS t1 ON t2.cid  =  t1.cid WHERE t1.name  =  "VLDB" AND t2.year  <  2005;
[{'SUM ( t2.citation_num )': None}]