Hi all,
I have 1 table which need to store 7 days data in a row, I not sure
which table design will gain better performance in SELECT statement.
Desgin 1. 7 columns (day1, ..., day7) with char(4)
or
Desgin 2. 1 column (day_1_to_7) with char(28); to retrieve the data,
use substr function
Plz advise.
Thanks!
Whitepaper
1  1533 
Though it depends on your application, my thought is that your Design
1 will perform better and easy to maintain .. Design 1 will eliminate
the overhead of SUBSTR function
Cheers
Sathyaram www.db2click.com wh***********@y ahoo.com.tw (Jason) wrote in message news:<53******* *************** ****@posting.go ogle.com>... Hi all,
I have 1 table which need to store 7 days data in a row, I not sure
which table design will gain better performance in SELECT statement.
Desgin 1. 7 columns (day1, ..., day7) with char(4)
or
Desgin 2. 1 column (day_1_to_7) with char(28); to retrieve the data,
use substr function
Plz advise.
Thanks!
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