[mongodb_safe_update] 更新 MongoDB 数据库前提取所有会进行修改的内容，并返回。确认无误后再批量修改。建议在 Jupyter 中使用。#mongodb #pymongo

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[mongodb_safe_update] 更新 MongoDB 数据库前提取所有会进行修改的内容，并返回。确认无误后再批量修改。建议在 Jupyter 中使用。#mongodb #pymongo

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Last edited May 13, 2019

Created on May 13, 2019

This example demonstrates a safe workflow for updating MongoDB documents by previewing changes before applying them. It defines a class that copies affected documents into a temporary collection, applies the update query there, and samples a random subset of diffs for visual inspection using `pprint` and `jsondiff`. After manual review, the user confirms the batch write with PyMongo’s `bulk_write` and `ReplaceOne`, optionally cleaning up the temporary collection. The code uses `MongoClient`, `InsertOne`, and `count_documents` to manage the staged updates.

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