DB2 database design : physical design is important

The regular comment passed by DBA s  is “90 % of the overall db performance is based on the code written against it”

There is truth to this comment , and large amounts are written on optimising queries on DB2 databases. DB2  database design physical  supports logical database design

 This comment came up today at a team meeting . It turned out the developer wrote a query assuming an index existed – and the query reflected this assumption.  It turned out the index was missing

 Good physical design is important , and in most cases the DBA is responsible for either creating the physical design or signing off on the design

 Physical design is a  big topic including:

-data type choice

-normalization\denormalization

-index design

-multidimensional clustering

-partitioning

-Materialized query table

 A coder can only work the existing DB2 database design : logical and physical

 Source:Jack Vamvas(http://www.dba-db2.com)