Hi I have 2 collections and i want to join them and filter max value my data is like below // schemas row1 = {“topic_name”: “rating01”, “version”: “1”, “reg_dt”: “20220401 22:10:05”} row2 = {“topic_name”: “rating01”, “version”: “2”, “reg_dt”: “20220402 10:01:10”} row3 = {“topic_name”: “rating0…

[image] kIL_Yoon: If i only want to see the latest schema_version of topic in the meta collection, … Replace the existing $sort stage with this, in the pipeline: { $sort: { topic_name: 1, schema_version: -1 } },

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kIL_Yoon (lalala98) April 18, 2022, 12:53pm 5

Thank very much ! Saya