Purpose

This page guides you to get the the content of the too large SCC if there is one, for more information about SCC refer to Transaction Configuration Center - Information - Definition and impacts of the large Strongly Connected Component

Official documentation

Applicable in CAST Version
Release
Yes/No
8.3.x(tick)
8.2.x(tick)
8.1.x(tick)
8.0.x(tick)
Applicable RDBMS
RDBMS
Yes/No
Oracle Server (question) 
Microsoft SQL Server (question) 
CSS2(tick)
Details

You can get the content of the largest SCC, or since 8.2.0 the content of the N most large SCC, for this you can perform the following:

  1. If you are using an AIP version lower then 8.2.0 then run the following 2 queries on the KB:
     

     

    delete from SYS_SITE_OPTIONS where OPTION_NAME = 'GRAPH_SAVE_LARGEST_SCC_GROUP';
    Insert into SYS_SITE_OPTIONS(OPTION_NAME, OPTION_VALUE) values ('GRAPH_SAVE_LARGEST_SCC_GROUP', '1');

     

    Else run the following 2 queres on the KB for getting the content of the N most large SCC (available only since 8.2.0):

     

    delete from SYS_SITE_OPTIONS where OPTION_NAME = 'GRAPH_SAVE_LARGEST_SCC_GROUP';
    Insert into SYS_SITE_OPTIONS(OPTION_NAME, OPTION_VALUE) values ('GRAPH_SAVE_LARGEST_SCC_GROUP', 'N'); -- where N is any integer value > 1
  2. Relaunch results computation in TCC to populate
    - the FP_LargestSCC table if option value is 1
    - the FP_LargeSCC table if option value is > 1

    Only one of these 2 tables will be populated, meaning that if option value is > 1, the FP_LargestSCC table will never get populated.

  3. If option value is 1, the FP_LargestSCC table now contains in its only column Object_ID the list of all objects ID belonging to the largest SCC.
    If option value is > 1, the FP_LargeSCC table now contains in its columns SCC_Num and Object_ID the list of all objects ID belonging to the N largest SCCs, sorted by decreasing SCC size. 
    If the FP_LargestSCC table would have been filled instead, we would have had ( select Object_ID from FP_LargestSCC ) equals select Object_ID from FP_LargeSCC where SCC_Num=1 ). 

     

    Warning

    If option value is 1, only objects in the largest SCC group will be reported in FP_LargestSCC; if there are more than 1 excluded large SCC, you will only be able to investigate the largest one.

    If option value is N > 1 (available only since 8.2.0), objects in the N most large SCC groups will be reported in FP_LargeSCC, but N can be set as big as necessary for being able to investigate on any large SCC group.

  4. In order to list the content you can run the following:

    SELECT * 
    FROM   fp_largestscc

    As output you will get the Ids of objects involved in the LSCC, the bellow result illustrate one row of the output

     

    -- 452178
Notes/comments

 

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