要通过单个查询更新许多文档,请在MongoDB中使用 bulkWrite()。让我们创建一个包含文档的集合-
> db.demo760.insertOne({id:1,details:{Value1:100,Value2:50}});
{
"acknowledged" : true,
"insertedId" : ObjectId("5eb0309f5637cd592b2a4aee")
}
> db.demo760.insertOne({id:2,details:{Value1:60,Value2:70}});
{
"acknowledged" : true,
"insertedId" : ObjectId("5eb030a15637cd592b2a4aef")
}
> db.demo760.insertOne({id:3,details:{Value1:80,Value2:90}});
{
"acknowledged" : true,
"insertedId" : ObjectId("5eb030a15637cd592b2a4af0")
}
在find()方法的帮助下显示集合中的所有文档-
> db.demo760.find();
这将产生以下输出-
{ "_id" : ObjectId("5eb0309f5637cd592b2a4aee"), "id" : 1, "details" : { "Value1" : 100, "Value2" : 50 } }
{ "_id" : ObjectId("5eb030a15637cd592b2a4aef"), "id" : 2, "details" : { "Value1" : 60, "Value2" : 70 } }
{ "_id" : ObjectId("5eb030a15637cd592b2a4af0"), "id" : 3, "details" : { "Value1" : 80, "Value2" : 90 } }
以下是使用MongoDB中的一个查询来更新许多文档的查询-
> db.demo760.bulkWrite([
... {
... updateOne: {
... filter: {id: 1},
... update: {$set: {'details.Value1': 900, 'details.Value2': 500}},
... }
... },
... {
... updateOne: {
... filter: {id: 2},
... update: {$set: {'details.Value1': 1000, 'details.Value2': 2000}},
... },
... }
... ])
{
"acknowledged" : true,
"deletedCount" : 0,
"insertedCount" : 0,
"matchedCount" : 2,
"upsertedCount" : 0,
"insertedIds" : {
},
"upsertedIds" : {
}
}
在find()方法的帮助下显示集合中的所有文档-
> db.demo760.find();
这将产生以下输出-
{ "_id" : ObjectId("5eb0309f5637cd592b2a4aee"), "id" : 1, "details" : { "Value1" : 900, "Value2" : 500 } }
{ "_id" : ObjectId("5eb030a15637cd592b2a4aef"), "id" : 2, "details" : { "Value1" : 1000, "Value2" : 2000 } }
{ "_id" : ObjectId("5eb030a15637cd592b2a4af0"), "id" : 3, "details" : { "Value1" : 80, "Value2" : 90 } }