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问题描述
让我们假设以下架构:
{ '_id' : 'star_wars', 'count' : 1234, 'spellings' : [ { spelling: 'Star wars', total: 10}, { spelling: 'Star Wars', total : 15}, { spelling: 'sTaR WaRs', total : 5} ] }我可以通过这样做来更新计数和拼写之一:
I can update the count and one of the spellings by doing this:
db.movies.update( {_id: "star_wars", 'spellings.spelling' : "Star Wars" }, { $inc : { 'spellings.$.total' : 1, 'count' : 1 }} )但是这种形式的更新不适用于 upsert.即,如果我尝试使用不存在的 _id 或拼写不存在的 _id 进行更新(使用 upsert),则不会发生任何事情.
But this form of update doesn't work with upsert. i.e., if I try to update (with upsert) with an _id that doesn't exist, or with a spelling that doesn't already exist, nothing happens.
有没有一种解决方案可以让我在更新 ($inc) 子文档时进行 upsert?
Is there a solution that allows me to upsert when updating ($inc) a sub-document?
谢谢!
推荐答案不过,您可以稍微更改一下架构.如果您的文档如下所示:
You could change your schema a little, though. If your documents looked like this:
{ '_id' : 'star_wars', 'count' : 1234, 'spellings' : { 'Star wars': 10, 'Star Wars': 15, 'sTaR WaRs': 5 } }您的更新将变得如此简单:
Your updates would become as simple as:
db.movies.update({_id:"star_wars"},{$inc:{"spellings.Star Wars":1}},true)更多推荐
MongoDB:更新和子文档
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