topic DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporary table already in use [ in Qlik Replicate

DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporary table already in use [

iucv — Thu, 16 Mar 2023 07:49:21 GMT

When I checked my cdc tasks, I found that none of them were synchronized in real time. So I started to check the log, which shows "Failed executing drop table statement: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporary table already in use [1022307]" , So I deleted the session that was using the table in the oracle database, and successfully executed the drop table "SYSTEM"."attrep_changesDAOC7DA_0000155", but in the following period of time, a large number of this error appeared.
Do you guys have a solution to this error?

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

john_wang — Thu, 16 Mar 2023 09:04:04 GMT

Hello @iucv ,

Thanks for reaching out.

In general this is caused by Oracle connection not stable and the broken connections locked the net change table (like "attrep_changesDAOC7DA_0000155"). As the issue is happening on global temporary tables only, we'd like to suggest you to disable the use of global temporary table by adding an internal parameter createNetChangesTempTable on target Endpoint:

IF the problem persists please enable target_apply to Trace (or Verbose) and provide the task Diagnostics Packages (opening a support ticket, please do not attach them here as community is public), support team will help you to investigate further.

Hope this helps.

Regards,

John.

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

iucv — Tue, 21 Mar 2023 14:02:58 GMT

This is an effective solution and it did solve the problem for me with such configuration. However, its impact on performance is significant, which led me to replace the machine of the target database and optimize the stability of the database connection.

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

iucv — Tue, 21 Mar 2023 14:06:20 GMT

Also, I greatly appreciate your answer. It gave me the right direction.

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

KellyHobson — Mon, 07 Aug 2023 14:06:40 GMT

Setting internal parameter createNetChangesTempTable = False

Provides the desired workaround, but we recommend identifying the network drops causing these issues. The root cause is network not stable, make sure the network works fine then we may set it back to TRUE.

createNetChangesTempTable = True or enabled is the Oracle Target setting by default.

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

R2JOE — Thu, 18 Dec 2025 01:51:14 GMT

Hello, I have the same problem. Could you please advise me on how to optimize the stability of the Oracle connection?
Thank you!

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

john_wang — Fri, 19 Dec 2025 07:40:05 GMT

Hello @R2JOE ,

Does the option mentioned above not work in your case? Could you please elaborate on the issue or clarify your question?

Thank you.

John.

Re: DROP TABLE "SYSTEM"."attrep_changesDAOC7DA_0000155" [1020403] ORA-14452: attempt to create, alter or drop an index on temporar

jameswalker — Sat, 27 Dec 2025 15:40:10 GMT

This error usually means another session or background process is still holding the temporary table when the CDC task tries to drop it. Restarting the affected CDC task or the replication service often clears those stuck sessions cleanly. It’s also a good idea to check for any orphaned Oracle sessions before the task runs. Make sure your CDC tool is on a supported version and that any recommended patches are applied. If the issue keeps repeating, it may be a known bug, and reaching out to vendor support is usually the best next step. Regularly reviewing logs from a central website or dashboard, similar to setups discussed on Neefox, can help catch this early.