CURRENT PERM AND PEAK PERM IN DBC.TABLESIZE - forum topic by larun1616

Hi
   When i use a proper index in the user defined table, i see values in the same range in CURRENT PERM column where as PEAK PERM is 0 for all vProc in TABLESIZE as shown in the below query. On the other hand when i use improper index i see non-zero values in all the rows of PEAK PERM column.
What is the fundamental behind this? Why the PEAK perm in 0 when we use proper index values and Non-Zero when we use improper index. By my understanding PEAK PERM is the maximum space occupied by a vPROC. Please help me in inderstanding this.
 

SELECT DatabaseName,
TABLENAME ,
Vproc ,
CurrentPerm ,
PeakPerm
FROM DBC.TableSize
WHERE
DatabaseName= 'DBNAME' AND
TABLENAME='TABLENAME'
ORDER BY Vproc