关于生产模式

[leocn2041]

在切换到production模式后，导入资料正常，在Query的时候，Couldn't come up with an answer。
控制台提示The query is empty. This will result in a zero score for all documents.
An error occurred while processing the query: ValueError: Expected where to have exactly one operator, got {} in query.

请问是什么原因呢？