Hi! I happily use comments to add somehow structured information to documents. The most frequent case is to add new "tagged" attributes to documents holding instances of the XWiki.XWikiUsers class. I'm sure there must be better ways of doing that, but I've had no time yet to go deeper into them, and I keep surviving that way. What I'm not able to do is to select a set of documents not containing a given string in any of the instances of XWiki.XWikiComments. Doing this... select doc.fullName from Document as doc, doc.object(XWiki.XWikiComments) as note where doc.parent like '%XWikiIDIS%' and length(doc.parent)=19 and doc.parent not like '%Area%' and doc.parent not like '%Committee%' and doc.parent not like '%Metagroup%' and doc.name not like '%Evidences%' and doc.name not like '%OI' and doc.parent not like '%DirectionBoard%' and doc.translation = 0 and note.comment not like '%IDIS Group Leader%' order by doc.parent" I get as many entries of each document as comments not containing '%IDIS Group Leader%' are held by that document. But, please, how could I get one entry for each document not containing that string in any of its comments? Thanks for your help! -- Ricardo Rodríguez Research Management and Promotion Technician Technical Secretariat Health Research Institute of Santiago de Compostela (IDIS) http://www.idisantiago.es