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We don't use @NonNull constraint for active objects. We need to verify the active objects record every time we use it anyway. Jira doesn't allow us to create foreign key constraints on issue table, user table. A user may create a reminder on an issue, and after that both the user and the issue may be deleted while the add-on is disabled temporarily. So we always need to verify data we read. We verify whether the user exist, issue exist. Adding a  @NonNull constraint on issue id or user key will not save us. Also as soon as we add a @NonNull constraint we need to hardcode name of these columns when creating active object records, we don't like this. 

Scheduled Tasks & Locking

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