select * vs select column

Question

If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O

Answer 1

I think there is no exact answer for your question, because you have pondering performance and facility of maintain your apps. Select column is more performatic of select *, but if you is developing an oriented object system, then you will like use object.properties and you can need a properties in any part of apps, then you will need write more methods to get properties in special situations if you don't use select * and populate all properties. Your apps need have a good performance using select * and in some case you will need use select column to improve performance. Then you will have the better of two worlds, facility to write and maintain apps and performance when you need performance.