Oracle DateTime Format

Display dates in query output
alter session set NLS_DATE_FORMAT = 'MM/DD/YYYY HH24:MI:SS'

Insert dates into table
insert into foo values ( to_date( '04/01/2002', 'MM/DD/YYYY HH24:MI:SS' ) );

HH     hour (1-12)

HH24   hour (0-23)

MI     minute

SS     second

SSSSS  seconds past midnight (0-86399)

Posted 4:07 PM    |    0 comments    |    Permalink   

SQL GroupBy

Never realized you could get the count and sum of many different columns in a query. The trick is that everything in the "select" clause must be in the "group by" clause. When using the group by, think of it like jamming all those columns together - as long as there's something unique in at least one of the columns, it'll come out as a different group.

select    [a,b,c...] , sum(d), sum(e), count(f)

from      tableA, tableB 

where     tableA.ID = tableB.ID

group by  [a,b,c...]

Posted 4:03 PM    |    0 comments    |    Permalink