SQL if/else help

Question

Can somebody help me with a query.
select name, isdefault, display_value  from v$parameter
where name in ( 'memory_target' , 'sga_target', 'statistics_level') order by name;
If memory_target is set non-zero, print AMM Else if sga_target is set non-zero
and statistics_level is TYPICAL or ALL, print ASMM.
Thanks to all who answer

Answer 1

Hi,
One way is to pivot the data, like this:
WITH    relevant_data    AS
    SELECT  name
    ,       display_value
    FROM    v$parameter
    WHERE   name    IN ( 'memory_target'
                       , 'sga_target'
                       , 'statistics_level'
SELECT    CASE
              WHEN  memory_target != '0'
                  THEN  'AMM'
              WHEN  sga_target        != '0'
              AND   statistics_level  IN ('ALL', 'TYPICAL')
                  THEN  'ASMM'
          END     AS amm_or_asmm
FROM      relevant_data
PIVOT     ( MIN (display_value)
            FOR name IN ( 'memory_target'    AS memory_target
                        , 'sga_target'       AS sga_target
                        , 'statistics_level' AS statistics_level