Column width convergation with Index performance
411951Sep 30 2010 — edited Oct 3 2010Hi experts,
Does anyone had calculated how the length of column width effects index performance?
For example if i had IOT table emp_iot with columns:
(id number,
job varchar2(20),
time date,
plan number)
Table key consist of(id, job, time)
Column JOB has fixed list of distinct values ('ANALYST', 'NIGHT_WORKED', etc...).
What performance increase i could expect if in column "job" i would store not names but concrete numbers identifying job names.
For egz.: i would store "1" instead 'ANALYST' and "2" instead 'NIGHT_WORKED'.
Thanks for replies.