Custom created database index in AO_60DB71_LEXORANK table gets dropped during Jira startup

Not a bug, this is expected behavior of the AO library, see comment below.

Issue Summary

Custom created database index in AO_60DB71_LEXORANK table gets dropped during Jira startup

Steps to Reproduce

1. Create a custom database index in Lexorank table, e.g.:

   CREATE INDEX "index_ao_60db71_lex_Idx" ON "AO_60DB71_LEXORANK" (ID, LOCK_HASH, LOCK_TIME);

2. Restart Jira

Expected Results

The index is retained in the database after the restart.

Actual Results

The index gets removed during the startup.

Enabled SQL logging shows "DROP INDEX" command executed during startup in atlassian-jira.log:

2020-02-26 12:41:46,992 active-objects-init-JiraTenantImpl{id='system'}-0 DEBUG anonymous     [n.java.ao.sql] DROP INDEX public."index_ao_60db71_lex_Idx"

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available