1db.getCollection('table').aggregate2([ {$match:{"a" : {$gt:"2018-01-01 08:24:35"}}},3{ $unwind: {path: '$fillDocArray(subDoc)'}},4{ $project: { 'b':1,5'c':1,6'd':1,7'e': 1,8another_a: '$subDoc.subfield1',9another_b:'$subDoc.subfield'} }10])...
[ "$status", "applied" ] }, { _id: "_id", title_number: "$title_number", status: "$status", updated: "$updated", rev_num: "$rev_num", revs: "$revs" }, "$$REMOVE" ] } }, applied_sub_doc: { $push: "$revs" } }, }, // flatten array in $applied_sub_doc prop ...
たとえば、 objがobjectであるSELECT * FROM myCol GROUP BY a AGGREGATE MIN(obj) as minでは、このエラーが発生します。 解決手順:適切なタイプの列でのみ、Aggregate 関数を使用します。 arrayまたはobject内の値を集計する場合は、UNWindows または FLATTEN データソース キーワードを使用しま...
Find slow running queries, investigate, and fix MongoDB queries to speed up performance. Profiling data for find and aggregate queries is presented in a format that’s easy to understand and all in one place. Spot missing indexes instantly. ...
Find slow running queries, investigate, and fix MongoDB queries to speed up performance. Profiling data for find and aggregate queries is presented in a format that’s easy to understand and all in one place. Spot missing indexes instantly. ...
聚合管道 MongoDB的聚合框架模型建立在数据处理管道这一概念的基础之上。文档进入多阶段管道中，管道将文档...
If no match is found, the array will be empty; otherwise, it will contain one or more documents from the customers collection. Additional Notes: Unwind Arrays:If you want to flatten the array created by $lookup into individual documents, you can use $unwind to expand each document in the ...
Query Profiler Find slow running queries, investigate, and fix MongoDB queries to speed up performance. Profiling data for find and aggregate queries is presented in a format that’s easy to understand and all in one place. Spot missing indexes instantly. ...
Query Profiler Find slow running queries, investigate, and fix MongoDB queries to speed up performance. Profiling data for find and aggregate queries is presented in a format that’s easy to understand and all in one place. Spot missing indexes instantly. ...
When flattening arrays, column names are appended with an underscore and the ordinal value (<array_name>_<ordinal_location>). This property allows you to determine whether the first ordinal value in the series is either a 0 or a 1. For details, refer to FlattenArrayBase.* The new JSON...