Dear all, We cannot mix updating and non updating instructions in the same list, so instruction sequences like this are not allowed : ( db:add(any document from disk), for ... in ... return .... ) because db:add is a updating function. could you please explain me how I can use db:add, db:delete, etc... functions in a simple way ? best regards, Fabrice ETANCHAUD Senior Software Engineer edital Berkenlaan 1 B-1831 Brussels, Belgium <skype:fabrice.etanchaud?call> +32 2 716 32 32 general +32 2 716 32 20 fax fetanchaud@edital.com corsearch.com <http://www.corsearch.com/> | edital.com <http://www.edital.com/> Confidentiality Notice: This email and its attachments (if any) contain confidential information of the sender. The information is intended only for the use by the direct addressees of the original sender of this email. If you are not an intended recipient of the original sender (or responsible for delivering the message to such person), you are hereby notified that any review, disclosure, copying, distribution or the taking of any action in reliance of the contents of and attachments to this email is strictly prohibited. If you have received this email in error, please immediately notify the sender at the address shown herein and permanently delete any copies of this email (digital or paper) in your possession.