Task Query
The task query is one of the heaviest used and most powerful queries of the process engine API. Due to its rich feature set, it can also become complex in SQL and may perform badly.Disabling CMMN and Standalone Tasks
To perform transparent access checks, the task query joins the authorization table (ACT_RU_AUTHORIZATION). For any kind of process-related filters, it joins the process definition table (ACT_RE_PROCDEF). By default, the query uses a left join for these operations. If CMMN and standalone tasks (tasks that are neither related to a BPMN process, nor a CMMN case) are not used, the engine configuration flags cmmnEnabled and standaloneTasksEnabled can be set to false. Then, the left joins are replaced by inner joins which perform better on some databases. See the configuration properties reference for details on these settings.