Re: R: Using Item Based recommenders as content based recommenders

[Sean Owen]

Yep I fixed that one a little while ago. :)

On Fri, Jul 24, 2009 at 8:22 AM, Claudia Grieco<gri...@crmpa.unisa.it> wrote:
> Thanks.
> Do you know of any fast way to obtain document-document similarity in Lucene 
> and write it to a text Mahout can read?
>
> Ah, while playing a bit with item based recommenders I found a bug in 
> MySQLJDBCDataModel
> // getNumPreferenceForItemsSQL
> "SELECT COUNT(1) FROM " + preferenceTable + " tp1 INNER JOIN " + 
> preferenceColumn + " tp2 " +
>          "ON (tp1." + userIDColumn + "=tp2." + userIDColumn + ") " +
>          "WHERE tp1." + itemIDColumn + "=? and tp2." + itemIDColumn + "=?");
>
>
> It should be
> "SELECT COUNT(1) FROM " + preferenceTable + " tp1 INNER JOIN " + 
> preferenceTable....