Database: academic
Question: return me the journal that has the most number of papers containing keyword " Relational Database " .
SQL:
SELECT t3.name FROM publication_keyword AS t4 JOIN keyword AS t1 ON t4.kid  =  t1.kid JOIN publication AS t2 ON t2.pid  =  t4.pid JOIN journal AS t3 ON t2.jid  =  t3.jid WHERE t1.keyword  =  "Relational Database" GROUP BY t3.name ORDER BY COUNT ( DISTINCT t2.title ) DESC LIMIT 1;