Performance tuning of a visualforce page
It's my strong belief that a developer should always keep the performance in the top of the priority list. As I was working on a big Visualforce page with lot of aggregations, I wondered how to get best performance out of APEX and VF. I went through Apex Code Best Practices and salesforce_visualforce_best_practices.pdf . Both were really helpful, until I ran into following statements. Apex Best Practice # 4 states " Use the power of the SOQL where clause to query all data needed in a single query. " Visualforce guide states " When writing Apex or SOQL for use with a Visualforce page: • Perform calculations in SOQL instead of in Apex, whenever possible. • Never perform DML inside a loop. • Filter in SOQL first, then in Apex, and finally in Visualforce " Now, I am confused on writing a single SOQL and do the aggregations such as (max,min, sum, avg) in APEX or writing mult...