I did not get this part." Another issue is the performance, because now you have at least two optimizers working and only one of them can handle the query". Two optimizers working!!? Is DBLINK queries behavior/access path different from non-dblink queries? Why dblink queries are slow compared to non-dblink queries considering both databases are in same location ? _____ From: Alfonso León [mailto:aleon68@xxxxxxxxx] Sent: Monday, April 30, 2007 1:15 PM To: Thotangare, Ajay (GTI) Subject: Re: DBLINKs in critical production system Hello: As people told you security is an issue here, but sometimes is needed, then you should for example if user a is the owner on dbA create synonyms and grant permitions only on the objects needed on that particular part of your application to a proxy user on dbA, an create the dblink over the proxy user. Another issue is the performance, because now you have at least two optimizers working and only one of them can handle the query. the other would become a slave. So you have to decide where should the query run. Regards On 4/30/07, Thotangare, Ajay (GTI) <Ajay_Thotangare@xxxxxx> wrote: Hi Group, I have a question about dblink. I always hear that - dblinks are not good in production system. - dblink , ohh!! not in critical production system - dblink are not safe Can anybody please let me know the reason for such comments on dblinks. regards, Ajay _____ If you are not an intended recipient of this e-mail, please notify the sender, delete it and do not read, act upon, print, disclose, copy, retain or redistribute it. Click here <http://www.ml.com/email_terms/> for important additional terms relating to this e-mail. http://www.ml.com/email_terms/ _____ -- Alfonso Leon