Mongodb 更新集合的方法到底有几种 (下) ？

更新方法

Mongodb 使用以下几种方法来更新文档 ， Mongodb V5.0+ 使用 mongosh 客户端：

  • db.collection.updateOne(<filter>, <update>, <options>)

  • db.collection.updateMany(<filter>, <update>, <options>)

  • db.collection.replaceOne(<filter>, <update>, <options>)

  • db.collection.findOneAndReplace(<filter>, <replacement>, <options>)

  • db.collection.findOneAndUpdate( <filter>, <update>, <options>)

  • db.collection.findAndModify(<document>)

  • db.collection.bulkWrite()

  • Bulk.find.replaceOne(<document>)

  • Bulk.find.update(<update>)

  • Bulk.find.updateOne(<update>)

  • Bulk.find.upsert()

批量写入

通过控制执行顺序执行多个写入操作。

bulkWrite() 接受一组写操作并执行每个操作。默认情况下，操作按顺序执行。

每组的操作数量不能超过数据库的maxWriteBatchSize的值。

maxWriteBatchSize的 默认值为100,000。该值显示在 hello.maxWriteBatchSize字段中。

sit_rs1:PRIMARY> rs.hello().maxWriteBatchSize
100000

db.collection.bulkWrite() 具有以下语法：

db.collection.bulkWrite([ <operation 1>, <operation 2>, ... ],{writeConcern : <document>,ordered : <boolean>}
)

operations: 一个数组 bulkWrite() 的写操作。 有效的操作是：

  • insertOne

  • updateOne

  • updateMany

  • deleteOne

  • deleteMany

  • replaceOne

该 ordered 参数指定是否 bulkWrite() 将按顺序或不按顺序执行操作。默认情况下，操作按顺序执行。

下面的代码代表了一个 bulkWrite() 有五个操作。

db.collection.bulkWrite([{ insertOne : <document> },{ updateOne : <document> },{ updateMany : <document> },{ replaceOne : <document> },{ deleteOne : <document> },{ deleteMany : <document> }]
)

默认 ordered : true 状态下，每个操作都会按顺序执行，从第一个操作 insertOne 到最​​后一个操作 deleteMany。

如果 ordered 设置为 false，则 mongod 可以对操作重新排序以提高性能。应用程序不应依赖于操作执行的顺序。

使用 时 ordered : false，操作结果可能会有所不同 !!!

以下示例向集合 user 插入 2 条 新记录 _id: 3, _id: 4， 更新 name: “user5” 用户，设置 age 等于57 ， 删除 user10, user11 用户（ 这里用了 deleteOne 方法，只会删除第一条匹配）。 最后再替换 name: “user8” 的文档 记录。 如下：

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 55, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf8"), "name" : "user10", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "age" : 61, "item" : { "A" : 113, "B" : 211 }, "number" : [ { "n1" : 5, "n2" : 4 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }# 插入2条新记录，更新1条，删除1条，替换1条
sit_rs1:PRIMARY> try {
...    db.user.bulkWrite( [
...       { insertOne: { document: { _id: 3, name: "user20", city: "sz", age: 26 } } },
...       { insertOne: { document: { _id: 4, name: "user21", city: "bj", age: 30 } } },
...       { updateOne: {
...          filter: { name: "user5" },
...          update: { $set: { age: 57 } }
...       } },
...       { deleteOne: { filter: { name: { $in: ["user10", "user11" ] } } } },
...       { replaceOne: {
...          filter: { name: "user8" },
...          replacement: { name: "user8", city: "sh", age: 66 }
...       } }
...    ] )
... } catch( error ) {
...    print( error )
... }
{"acknowledged" : true,"deletedCount" : 1,"insertedCount" : 2,"matchedCount" : 2,"upsertedCount" : 0,"insertedIds" : {"0" : 3,"1" : 4},"upsertedIds" : {}
}sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "city" : "sh", "age" : 66 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }

Bulk 构建器

Bulk.find.replaceOne(<document>) 将单个文档替换操作添加到批量操作列表中。使用该 Bulk.find() 方法指定确定要替换哪个文档的条件。Bulk.find.replaceOne() 方法将替换限制为单个文档。

Bulk() 批量操作构建器用于构造要为单个集合批量执行的写入操作列表。

要实例化构建器，请使用

  • 有序批量操作: db.collection.initializeOrderedBulkOp()
  • 无序批量操作: db.collection.initializeUnorderedBulkOp()。

有序操作

  • 通过有序操作列表，MongoDB 会串行执行列表中的写入操作。如果在处理其中一个写操作期间发生错误，MongoDB 将返回，而不处理列表中任何剩余的写操作。

无序操作

  • 通过无序操作列表，MongoDB 可以并行执行列表中的写入操作，也可以以不确定的顺序执行。如果在处理其中一个写操作的过程中发生错误，MongoDB将继续处理列表中剩余的写操作。
sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "city" : "sh", "age" : 66 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }# 实例化构建器， 无序批量操作 ！！！！！
sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();# 只执行单文档替换操作
sit_rs1:PRIMARY> bulk.find( { name: "user8" } ).replaceOne( { name: "user8", status: "Modified", age: 22 } );# 未执行 execute，数据还不会替换 ！！！！！！！！！！！
sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "city" : "sh", "age" : 66 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }# 执行 Bulk.execute() 执行由操作构建器构建的操作列表Bulk() 
sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 0,"nMatched" : 1,"nModified" : 1,"nRemoved" : 0,"upserted" : [ ]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "Modified", "age" : 22 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }

Bulk.find.update(<update>) 将multi更新操作添加到批量操作列表。该方法更新现有文档中的特定字段。

使用该Bulk.find()方法指定确定要更新哪些文档的条件。Bulk.find.update() 方法更新所有匹配的文档。

以下示例为 user 集合的 初始化操作构建器 Bulk() ，并将 user8、user20 更新操作添加到操作列表中， 如下：

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "Modified", "age" : 22 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();sit_rs1:PRIMARY> bulk.find( { name: "user8" } ).update( { $set: { status: "1", age: "33" } } );sit_rs1:PRIMARY> bulk.find( { name: "user20" } ).update( { $set: { age: "55" } } );sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "Modified", "age" : 22 }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : 26 }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 0,"nMatched" : 2,"nModified" : 2,"nRemoved" : 0,"upserted" : [ ]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "33" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }

Bulk.find.updateOne(<update>) 将单个文档更新操作添加到批量操作列表。

使用该Bulk.find()方法指定确定要更新哪个文档的条件。Bulk.find.updateOne() 方法将更新限制为单个文档。

以下示例为 user 集合的 初始化操作构建器 Bulk() ，并添加各种 updateOne() 操作到操作列表，如下：

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "33" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();sit_rs1:PRIMARY> bulk.find( { name: "user8" } ).update( { $set: { status: "1", age: "22" } } );sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 0,"nMatched" : 1,"nModified" : 1,"nRemoved" : 0,"upserted" : [ ]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }

Bulk.find.upsert() 将更新或替换操作的upsert选项设置为 true ， 并具有以下语法：

Bulk.find(<query>).upsert().update(<update>);
Bulk.find(<query>).upsert().updateOne(<update>);
Bulk.find(<query>).upsert().replaceOne(<replacement>);

将upsert选项设置为 时true:

  • 如果不存在与Bulk.find()条件匹配的文档，则更新或替换操作将执行插入。
  • 如果匹配的文档确实存在，则更新或替换操作将执行指定的更新或替换。

使用 Bulk.find.upsert() 具有以下写入操作：

Bulk.find.replaceOne()Bulk.find.updateOne()Bulk.find.update()

以下示例， 使用upsert选项执行替换 name: “user12” 的用户，如果不存在，则插入新文档 。

如果用替换操作 Bulk.find.upsert() 选项执行插入，插入的文档是替换文档。如果替换文档和查询文档均未指定_id字段，MongoDB 会添加该_id字段：

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();sit_rs1:PRIMARY> bulk.find( { name: "user12" } ).upsert().replaceOne(
...    {
...      name: "user12",
...      status: "0",
...      age: 12,
...    }
... );sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 1,"nMatched" : 0,"nModified" : 0,"nRemoved" : 0,"upserted" : [{"index" : 0,"_id" : ObjectId("64df3619aed0456fbb0e919e")}]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }
{ "_id" : ObjectId("64df3619aed0456fbb0e919e"), "name" : "user12", "status" : "0", "age" : 12 }

以下示例，使用 updateOne 方法更新一条记录 { name: “user12” }，如果不存在则执行插入。

如果更新操作为 Bulk.find.upsert() 选项执行插入，插入的文档是替换文档。如果替换文档和查询文档均未指定_id字段，MongoDB 会添加该_id字段。

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }
{ "_id" : ObjectId("64df3619aed0456fbb0e919e"), "name" : "user12", "status" : "0", "age" : 12 }sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();sit_rs1:PRIMARY> bulk.find( { name: "user12" } ).upsert().updateOne(
...    {
...      name: "user12",
...      status: "1",
...  age: 22,
...    }
... );sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 0,"nMatched" : 1,"nModified" : 1,"nRemoved" : 0,"upserted" : [ ]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }
{ "_id" : ObjectId("64df3619aed0456fbb0e919e"), "name" : "user12", "status" : "1", "age" : 22 }

使用 upsert() 多文档更新方法 Bulk.find.update()，如果没有文档符合查询条件，则更新操作插入单个文档。

如果更新操作为 Bulk.find.upsert() 选项执行插入，更新操作插入单个文档，其中包含该方法的查询文档中的字段和值。

sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }
{ "_id" : ObjectId("64df3619aed0456fbb0e919e"), "name" : "user12", "status" : "1", "age" : 22 }sit_rs1:PRIMARY> var bulk = db.user.initializeUnorderedBulkOp();sit_rs1:PRIMARY> bulk.find( { name: "user15" } ).upsert().update(
...    {
...      $setOnInsert: { "item" : { "A" : 111, "B" : 222 } },
...      $set: { status: "1", age: "50" }
...    }
... );sit_rs1:PRIMARY> bulk.execute();
BulkWriteResult({"writeErrors" : [ ],"writeConcernErrors" : [ ],"nInserted" : 0,"nUpserted" : 1,"nMatched" : 0,"nModified" : 0,"nRemoved" : 0,"upserted" : [{"index" : 0,"_id" : ObjectId("64df389daed0456fbb0e9944")}]
})sit_rs1:PRIMARY> db.user.find()
{ "_id" : ObjectId("64b8d2404b442dde59447cf4"), "name" : "user5", "age" : 57, "item" : { "A" : 112, "B" : 215 }, "number" : [ { "n1" : 7, "n2" : 8 }, { "n1" : 99, "n2" : 4 }, { "n1" : 4, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf2"), "name" : "user3", "age" : 30, "item" : { "A" : 113, "B" : 213 }, "number" : [ { "n1" : 1, "n2" : 8 }, { "n1" : 2, "n2" : 6 }, { "n1" : 2, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf6"), "name" : "user7", "age" : 45, "item" : { "A" : 116, "B" : 216 }, "number" : [ { "n1" : 6, "n2" : 6 }, { "n1" : 99, "n2" : 5 }, { "n1" : 7, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf3"), "name" : "user4", "age" : 45, "item" : { "A" : 111, "B" : 211 }, "number" : [ { "n1" : 99, "n2" : 6 }, { "n1" : 2, "n2" : 4 }, { "n1" : 3, "n2" : 6 } ] }
{ "_id" : ObjectId("64b8d2404b442dde59447cf5"), "name" : "chen", "status" : "Modified" }
{ "_id" : ObjectId("64b8d2404b442dde59447cf7"), "name" : "user8", "status" : "1", "age" : "22" }
{ "_id" : ObjectId("64db6285f386d37d5de1b830"), "name" : "user11", "age" : 50, "number" : 1 }
{ "_id" : 3, "name" : "user20", "city" : "sz", "age" : "55" }
{ "_id" : 4, "name" : "user21", "city" : "bj", "age" : 30 }
{ "_id" : ObjectId("64df3619aed0456fbb0e919e"), "name" : "user12", "status" : "1", "age" : 22 }
{ "_id" : ObjectId("64df389daed0456fbb0e9944"), "name" : "user15", "age" : "50", "item" : { "A" : 111, "B" : 222 }, "status" : "1" }

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