mongodb - 如何通过 Java 驱动程序使用 Mongodb 批量更新？

Question

我正在使用 Mongo Bulk Update，并使用其 Java 驱动程序 2.13。

    MongoClient mongo = new MongoClient("localhost", 27017);
    DB db = (DB) mongo.getDB("test");
    DBCollection collection = db.getCollection("collection");
    BulkWriteOperation builder = collection.initializeOrderedBulkOperation();
    builder.find(new BasicDBObject("_id", "1")).update(new BasicDBObject("_id", "1").append("name", "dev"));

我遇到以下异常:

Caused by: java.lang.IllegalArgumentException: Update document keys must start with $: _id
at com.mongodb.DBCollectionImpl$Run.executeUpdates(DBCollectionImpl.java:769)
at com.mongodb.DBCollectionImpl$Run.execute(DBCollectionImpl.java:734)
at com.mongodb.DBCollectionImpl.executeBulkWriteOperation(DBCollectionImpl.java:149)
at com.mongodb.DBCollection.executeBulkWriteOperation(DBCollection.java:1737)
at com.mongodb.DBCollection.executeBulkWriteOperation(DBCollection.java:1733)
at com.mongodb.BulkWriteOperation.execute(BulkWriteOperation.java:93)

Answer 1

错误的原因是因为在进行更新时必须使用更新运算符。请参阅http://docs.mongodb.org/manual/reference/operator/update/获取更新操作符列表。

从您的示例中，我发现您将名称字段设置为“dev”，因此您需要使用 $set 运算符，如下所示:

builder.find(new BasicDBObject("_id", "1"))
       .update(new BasicDBObject("$set", new BasicDBObject("name", "dev")));