如何使用mongoexport 导出distinct 不重复的column value 值
MongoDB: export distinct column value
由 余生颓废 提交于 2021-02-07 18:22:32
问题
Anyone have idea how to export distinct column value on mongodb using mongoexport command.
Command: db.coll.distinct("uid");
The solution i have tried is :
mongoexport --csv -d db -c collection -q '{distinct: "collection", "key": "uid"}' -f "uid" -o distinctUid.csv
回答1:
It's not possible to do it this way. distinct is a database command, and --query option allows to use only a query to filter documents.
If you are using mongodb v3.4 or later, you can use views to aggregate your collection and export it from the view.
First create the view in mongo shell:
db.createView("distinctCollectionUid", "collection", [{ $group: { _id: "$uid"}}]);
Then export it:
mongoexport -d db -c distinctCollectionUid --type=csv -f "_id" -o distinctUid.csv
回答2:
its working for me.
Example:
First create view:
db.createView("distinctCollectionBI2_Style( BI2_Style is key which value must distinc)","best_seller_data(your collection name)", [{ $group: { _id: "$BI2_Style"}}]);
Then export:
mongoexport -d best-seller(db name) -c distinctCollectionBI2_Style --type=csv -f "_id" -o Desktop/pretr/style.csv
来源：https://stackoverflow.com/questions/46560326/mongodb-export-distinct-column-value