> Can I use an index on a varchar column to optimize the SELECT queries
> that
> use " column LIKE 'header%'  "?
    Yes
> If yes what is the best tree algotithm to use ?
    Btree
    Note that if you want case insensitive matching you need to make an index
on lower(column) and SELECT WHERE lower(column) LIKE 'header%'
    Locales may bite you.