where pc.status != 2 and (startDate between pc.projectStartDate and pc.projectEndDate or endDate between pc.projectStartDate and pc.projectEndDate)
-----------------------------这样也可以------------------------------------------------------
where pc.status != 2 and (( startDate between pc.projectStartDate and pc.projectEndDate) or (endDate between pc.projectStartDate and pc.projectEndDate))
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这个问题的分类应该是数据库软件编程的。