db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Dyre.Tjeldv...@Sun.COM
Subject Question about FetchDescriptor.materialized_cols
Date Sun, 10 Dec 2006 14:59:03 GMT
Today this is an int[] but it appears to be used as a boolean. A
possible explanation for this can be found in a comment in
StoredPage.java:

                // RESOLVE (mikem) - right now value of entry is useless, it
                // is an int so that in the future we could cache the offset
                // to fields to improve performance of getting to a column 
                // after qualifying.
                materializedCols[col_id] = offset_to_row_data;

Can someone (mikem?) explain a bit more about this optimization and
what it would take to implement it? What would the potential gains be?
Is it a JIRA for this?

-- 
dt


Mime
View raw message