Manoj, This is a problem with the full refresh of an MV. The refresh initially truncates the table and then issues a full refresh. To resolve this problem, here are some steps:
Create the MV as a table first and then build the MV with "ON PREBUILT TABLE" clause. When created this way the drop snapshot (or MV) command does __not__ drop the segment; the table remains. Before doing the full refresh, drop the snapshot Copy the underlying table to a new name Then recreate a snapshot wth ON PREBUILT TABLE clause. Do a full refresh. While the full refresh is going on, you can refer to the copied table for the previous data. I did a presentation at IOUG Live this year which is along similar lines - "Painless Alter of Master Table in Replication", which you can find on my website, www.proligence.com. Hope this helps. Arup ----- Original Message ----- To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Tuesday, June 03, 2003 9:19 AM > Hi All, > > I have a mview(Materialized View) that i refresh > ONDEMAND. This Mview takes 15 minutes in refresh as it > involves a complex query and lots of data in master > table. But as soon as the refresh starts old data gets > deleted from the mview and there is no data in mview > untill the refresh is complete. As i m querying the > mview in my scripts i get no data if some request is > sent during that refresh interval. Can we keep this > old data untill new data gets populated? Or is there > anyway that we can reduce this time period for which > there is no data in mview? > > Thanks in advance > > Manoj Ahuja > > __________________________________ > Do you Yahoo!? > Yahoo! Calendar - Free online calendar with sync to Outlook(TM). > http://calendar.yahoo.com > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Manoj Ahuja > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Arup Nanda INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
