Walter K wrote: > > Hi, > > Could someone tell me what the "HIDDEN" columns option > is in the DBMS_STATS.GATHER_SCHEMA_STATS and > DBMS_STATS.GATHER_TABLE_STATS procedures? I don't seem > to find any explanation anywhere about its purpose. > > Thanks again. > -w >
I would guess that 'hidden' columns may more or less have to do with the object option, which seems (if sys.col$ is to be believed) to sometimes present as a single aggregated column what is indeed traditional 'split' columns. Another possibility might be function-based indexes. They create dummy columns in dba_ind_columns, those dummy (and therefore hidden) columns might be used when gathering stats. Just wild ideas. -- Regards, Stephane Faroult Oriole Ltd -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Stephane Faroult INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- 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).
