ups, sorry, here is the full query:
select
t.schemaname,
t.tablename,
t.createdate as tables_createdate, t.createtime as tables_createtime,
t.alterdate as tables_alterdate, t.altertime as tables_altertime,
c.createdate as columns_createdate, c.createtime as columns_createtime,
c.alterdate as columns_alterdate, c.altertime as columns_altertime,
c.columnname,
c.default
from tables t, columns c
where t.createdate <= c.createdate and t.createtime < c.createtime and t.tablename = c.tablename and t.schemaname = c.schemaname and t.schemaname = 'your_DB_User' and c.default is null