select
  A.inst_id,                               -- INST_ID NUMBER
  A.sgasz,                                 -- SGA_SIZE NUMBER
  round((A.sgasz / A.base_sgasz), 4),      -- SGA_SIZE_FACTOR NUMBER
  decode(                                  -- ESTD_DB_TIME NUMBER
    A.base_estd_dbtime,0,to_number(null), round(A.base_dbtime * round((A.dbtime / A.base_estd_dbtime), 4), 0)),
  decode(                                  -- ESTD_DB_TIME_FACTOR NUMBER
    A.base_estd_dbtime,0,to_number(null), round((A.dbtime / A.base_estd_dbtime), 4)),
  decode(                                  -- ESTD_PHYSICAL_READS NUMBER
    A.base_estd_phy_reads,0,to_number(null), round(A.base_phy_reads * round((A.estd_physical_reads / A.base_estd_phy_reads), 4), 0)) 
from
  x$kmgsbsadv A
order by
  A.inst_id,
  A.sgasz