对带有mongoDB GODriver的文档使用$push运算符，而无需创建单独的数组

import (
    "go.mongodb.org/mongo-driver/bson"
    "go.mongodb.org/mongo-driver/mongo"
    "go.mongodb.org/mongo-driver/mongo/options"
)

client, err := mongo.Connect(context.Background(), options.Client().ApplyURI("mongodb://localhost:27017"))
if err != nil {
    // 处理错误
}

collection := client.Database("your_database").Collection("your_collection")

filter := bson.D{{"field", "value"}}
update := bson.D{{"$push", bson.D{{"arrayField", "newElement"}}}}

_, err := collection.UpdateOne(context.Background(), filter, update)
if err != nil {
    // 处理错误
}