Re: External table performance

 Thanks Kellyn and ours is Multitenant Database and so having two PDBS and will check the second one. Sanjay

    On Friday, January 12, 2018, 6:12:11 PM EST, Kellyn Pot'Vin-Gorman <dbakevlar_at_gmail.com> wrote:  

 I’d only just heard of it recently, but the DBA experiencing it said it was any pull from external table to do bulk loads.  There’s a number of bugs in Oracle support for the search criteria: “12.1 external table read”

Bug 21553593  20+ million directory objects causing slow reads from external tables

Bug 19597583  "external table reads" during local PDB 

On Fri, Jan 12, 2018 at 4:58 PM Sanjay Mishra <smishra_97_at_yahoo.com> wrote:

 Kellyn
thanks for the information. Do you have more details about the bug ?  Sanjay

    On Friday, January 12, 2018, 4:22:39 PM EST, Kellyn Pot'Vin-Gorman <dbakevlar_at_gmail.com> wrote:  

 Be aware, there is also a known bug in 12.1 with external tables causing performance issues. Length 
On Fri, Jan 12, 2018 at 2:31 PM Sanjay Mishra <dmarc-noreply_at_freelists.org> wrote:

 Mark
Oracle 12.1.2 and it is Single Node RAC instance and is Enterprise Edition. The issue with Select is where Clause for 2-3 column where Index can definitely be helpful but External table dont allow index. Select was Tried with Parallel but no difference in terms of performance. One option trying is MV and as data is not much but table is extensively used for various purpose. Sanjay

    On Friday, January 12, 2018, 2:29:48 PM EST, Powell, Mark <mark.powell2_at_dxc.com> wrote:    

Sanjay, you did not identify your Oracle version and edition nor post the actual code you have an issue with but consider the following.

I do not have access to a server where I can test right now but I believe that you can select from an external table using parallel query if you are on EE.

Mark PowellDatabase Administration(313) 592-5148

From: oracle-l-bounce_at_freelists.org <oracle-l-bounce_at_freelists.org> on behalf of Sanjay Mishra <dmarc-noreply_at_freelists.org> Sent: Friday, January 12, 2018 2:23:40 PM To: Oracle-L Freelists
Subject: External table performance Can someone share the Tuning activites that can be done for Selecting data from External table in 12c (12.1)? I am working on project that is getting every 6hourly data as flat file from external source and then has to be selected from ORacle table for some processing. Data is only 50K records but Select is taking time. It is Local Storage where File is located. I don;t think we can have indexes yet and so checking experience from the experts. TxSanjay

-- 
  


|   |

|    |   |  Kellyn Pot'Vin-Gorman about.me/dbakevlar  |


|   |


    
-- 
  


|   |

|    |   |  Kellyn Pot'Vin-Gorman about.me/dbakevlar  |


|   |


    
--
http://www.freelists.org/webpage/oracle-l