That was rhetorical, I spool all the time. I almost mentioned some points but figured whatever could be encompassed in anonymous block also... if you favored that route. Creating the sql statements dynamically just seems quicker and easier for quick execution... but it's not worth discussing the ins and outs of this. It is good to know both ways and build on both. Joel Patterson Database Administrator joel.patterson@xxxxxxxxxxx x72546 904 727-2546 -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Powell, Mark D Sent: Tuesday, March 27, 2007 1:42 PM To: oracle-l@xxxxxxxxxxxxx Subject: RE: Any quick way to remove histograms? One advantage of spooling a file and executing the file is that you can have the execution file also create a spool file with the commands and results in the output. This allows verification that the task did run successfully. Script files also allow copying and pasting of individual commands when only a partial update is desired or some other manipulation of the parameters is desired for a specific statement. In another word, flexibility. -- Mark D Powell -- Phone (313) 592-5148 -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Joel.Patterson@xxxxxxxxxxx Sent: Tuesday, March 27, 2007 11:17 AM To: breitliw@xxxxxxxxxxxxx; Brandon.Allen@xxxxxxxxxxx Cc: oracle-l@xxxxxxxxxxxxx Subject: RE: Any quick way to remove histograms? Why indeed? :) Joel Patterson Database Administrator joel.patterson@xxxxxxxxxxx x72546 904 727-2546 -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Wolfgang Breitling Sent: Tuesday, March 27, 2007 9:20 AM To: Brandon.Allen@xxxxxxxxxxx Cc: oracle-l@xxxxxxxxxxxxx Subject: RE: Any quick way to remove histograms? Why spool, capture and then execute when you can do it all in one: declare l_ndv number; l_dummy number; l_srec dbms_stats.statrec; begin for r in (select owner, table_name, column_name, null partition_name from DBA_TAB_COL_STATISTICS histogram <> 'NONE' [ and possibly other criteria ] union all select owner, table_name, column_name, partition_name from DBA_PART_COL_STATISTICS histogram <> 'NONE' [ and possibly other criteria ] ) loop dbms_stats.get_column_stats ( ownname => r.owner, tabname => r.table_name, colname => r.column_name, partname => r.partition_name, stattab => null, statid => null, distcnt => l_ndv, density => l_dummy, nullcnt => l_dummy, srec => l_srec, avgclen => l_dummy); dbms_stats.set_column_stats ( ownname => r.owner, tabname => r.table_name, colname => r.column_name, partname => r.partition_name, distcnt => l_ndv); end loop; end; and no fighting with quotes :-) I believe if you have subpartitions you will need to export the statistics to a stattab table, manipulate the statistics there and then re-import as there is no set_column_stats for subpartitions. At 06:23 PM 3/26/2007, Allen, Brandon wrote: >At first I was thinking that Alberto's procedure would still be required >for retrieving the current stats and then resetting just the distcnt >value. However, after thinking it through for a while, I realized what >you were probably both thinking the whole time, which is that with this >simplified method, you can just use a simple SELECT statement on >all_tab_col_statistics to retrieve the current num_distinct value and >plug it into the set_column_stats procedure for all columns that >currently have histograms, thereby creating a script that can be used to >very quickly remove all existing histograms. It took me a while to get >all the single quotes just right, but here is the working version for >anyone else that might find it helpful: > >select 'execute dbms_stats.set_column_stats(''' || owner || ''',''' || >table_name || ''',''' || column_name || ''', distcnt=>''' || >num_distinct || ''');' from all_tab_col_statistics where histogram <> >'NONE'; > >Sample Output: > >---------------------------------------------------------------------- >execute dbms_stats.set_column_stats('SCOTT','T','C1', distcnt=>'2421'); >execute dbms_stats.set_column_stats('SCOTT','T','C2', distcnt=>'2425'); >execute dbms_stats.set_column_stats('SCOTT','T','C3', distcnt=>'2421'); > > >Thanks again to Wolfgang and Alberto! > >Regards, >Brandon > > > > >-----Original Message----- >From: Alberto Dell'Era [mailto:alberto.dellera@xxxxxxxxx] >Sent: Friday, March 16, 2007 4:43 PM >To: breitliw@xxxxxxxxxxxxx >Cc: Allen, Brandon; Oracle-L@xxxxxxxxxxxxx >Subject: Re: Any quick way to remove histograms? > >Much simpler :) - interesting. > > >On 3/16/07, Wolfgang Breitling <breitliw@xxxxxxxxxxxxx> wrote: > > > > I also did a quick check and just using > > > > exec > > dbms_stats.set_column_stats(user,'table_name',colname=>'column_name',d > > istcnt=> > > <num_distinct>); > > > > will remove the histogram without removing the low_value and >high_value. > > > > > > > > At 01:40 PM 3/16/2007, Alberto Dell'Era wrote: > > >On 3/16/07, Allen, Brandon <Brandon.Allen@xxxxxxxxxxx> wrote: > > >>Is there any faster way to remove histograms other than re-analyzing > > > >>the table? I want to keep the existing table, index & column stats, > > > >>but with only 1 bucket (i.e. no histograms). > > > > > >You might try the attached script, that reads the stats using > > >dbms_stats.get_column_stats and re-sets them, minus the histogram, > > >using dbms_stats.set_column_stats. > > > > > >I haven't fully tested it - it's only 10 minutes old, even if I have > > >slightly modified for you another script I've used for quite some > > >time - and the spool on 10.2.0.3 seems to confirmthat the histogram > > >is, indeed, removed, while all the other statistics are preserved. I > > >have also reset density to 1/num_distinct, that is the value you get > > >if no histogram is collected. > >Privileged/Confidential Information may be contained in this message or >attachments hereto. Please advise immediately if you or your employer >do not consent to Internet email for messages of this kind. >Opinions, conclusions and other information in this message that do not >relate to the official business of this company shall be understood as >neither given nor endorsed by it. > >-- >//www.freelists.org/webpage/oracle-l Regards Wolfgang Breitling Centrex Consulting Corporation www.centrexcc.com ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l