Calling all Apps DBAs doing 11i to R12.x upgrades

At this time of the year during holidays, the Apps DBA community is busy doing upgrades as longer downtimes are possible.  In case you are facing any issues, please feel free to write to me at my email: oracleappstechnology@gmail.com .  I will be glad to hear from you and help you.

11i pre-upgrade data fix script ap_wrg_11i_chrg_alloc_fix.sql runs very slow

We are currently upgrading one of our ERP instances from 11.5.10.2 to R12.2.5.  One of the pre-upgrade steps is to execute the data fix script ap_wrg_11i_chrg_alloc_fix.sql.  However, this script has been running very very slow. After 4 weeks of monitoring, logging SRs with Oracle, escalating etc., we started a group chat today with our internal experts.  We had Ali, Germaine, Aditya, Mukhtiar, Martha Gomez and Zoltan.  I also invited our top notch EBS Techstack expert John Felix. After doing explain plan on the sql, Based on the updates being done by the query I predicted that it will take 65 days to complete.

John pointed out that the query was using the index AP_INVOICE_DISTRIBUTIONS_N4  that had a very high cost.  We used an sql profile that replaced AP_INVOICE_DISTRIBUTIONS_N4  with AP_INVOICE_DISTRIBUTIONS_U1.  The query started running faster and my new prediction was that it would complete in 5.45 days.

John mentioned that now another select statement was using the same index AP_INVOICE_DISTRIBUTIONS_N4 that had a very high cost.

After discussing among ourselves, we decided to drop the index, run the script and re-create the index. Aditya saved the definition of the index and dropped it.

DBMS_METADATA.GET_DDL('INDEX','AP_INVOICE_DISTRIBUTIONS_N4','AP')
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

  CREATE INDEX "AP"."AP_INVOICE_DISTRIBUTIONS_N4" ON "AP"."AP_INVOICE_DISTRIBUTIONS_ALL" ("ACCOUNTING_DATE")
  PCTFREE 10 INITRANS 11 MAXTRANS 255 COMPUTE STATISTICS
  STORAGE(INITIAL 131072 NEXT 131072 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "APPS_TS_TX_IDX"

1 row selected.

SQL> drop index AP.AP_INVOICE_DISTRIBUTIONS_N4;

Index dropped.

The updates started happening blazing fast.  The whole thing got done in 39 minutes and we saw the much awaited:

SQL> set time on
16:34:16 SQL> @ap_wrg_11i_chrg_alloc_fix.sql
Enter value for resp_name: Payables Manager
Enter value for usr_name: 123456
-------------------------------------------------------------------------------
/erp11i/applcsf/temp/9570496-fix-16:34:40.html is the log file created
-------------------------------------------------------------------------------

PL/SQL procedure successfully completed.

17:13:36 SQL>

From 65 days to 5.45 days to 39 minutes.  Remarkable.  Thank you John for your correct diagnosis and solution.