红帽全球峰会2.4. Indexing Foreign Keys
Some databases, for instance Oracle and Postgres, do not automatically create an index for each foreign key. This can result in deadlocks occurring. To avoid this situation it is necessary to create indexes on some of the columns that are referenced in foreign key constraints.
Indexes should be created on the following columns to avoid possible deadlocks and improve query performance:
Human-Task schema:
- Task.processinstanceid
- task.processid
- task.status
- task.archived
- task.workitem
- i18ntext.language
Core engine schema:
- eventtables.instanceid
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