Question

我正在尝试使用以下结构更新我的mongo集合

{
    "_id" : "T6GqWsi9qSxnyGzgC",
    "spec_name" : "test",
    "version" : "test",
    "message_type" : "test",
    "message_trigger" : "test",
    "segments" : [
        {
            "segment_id" : "MSH",
            "sequences" : [
                {
                    "dataType" : "ST",
                    "optionality" : "R",
                    "name" : "Field Seperator"
                },
                {
                    "dataType" : "ST",
                    "optionality" : "R",
                    "name" : "Encoding Characters"
                },
                {
                    "dataType" : "HD",
                    "optionality" : "O",
                    "name" : "Sending Application"
                },
                {
                    "dataType" : "HD",
                    "optionality" : "O",
                    "name" : "Sending Facility"
                },
                {
                    "dataType" : "HD",
                    "optionality" : "O",
                    "name" : "Receiving Application"
                },
                {
                    "dataType" : "HD",
                    "optionality" : "O",
                    "name" : "Receiving Facility"
                },
                {
                    "dataType" : "TS",
                    "optionality" : "O",
                    "name" : "Data/Time Of Message"
                },
                {
                    "dataType" : "ST",
                    "optionality" : "O",
                    "name" : "Security"
                },
                {
                    "dataType" : "CM",
                    "optionality" : "R",
                    "name" : "Message Type"
                },
                {
                    "dataType" : "ST",
                    "optionality" : "R",
                    "name" : "Message Control ID"
                },
                {
                    "dataType" : "PT",
                    "optionality" : "R",
                    "name" : "Processing ID"
                },
                {
                    "dataType" : "NM",
                    "optionality" : "O",
                    "name" : "Sequence ID"
                },
                {
                    "dataType" : "ST",
                    "optionality" : "O",
                    "name" : "Continuation Pointer"
                },
                {
                    "dataType" : "ID",
                    "optionality" : "O",
                    "name" : "Accept Acknowledgment Type"
                },
                {
                    "dataType" : "ID",
                    "optionality" : "O",
                    "name" : "Application Acknowledgment Type"
                },
                {
                    "dataType" : "ID",
                    "optionality" : "O",
                    "name" : "Country Code"
                },
                {
                    "dataType" : "ID",
                    "optionality" : "O",
                    "name" : "Character Set"
                },
                {
                    "dataType" : "CE",
                    "optionality" : "O",
                    "name" : "Principal Language Of Message"
                }
            ]
        }
    ],
    "segment_groups" : [
        {
            "grouping_id" : 692335,
            "segments" : [
                {
                    "segment_id" : "test",
                    "group_segment_id" : 597268,
                    "sequences" : [ ]
                }
            ]
        }
    ]
}

我希望附加{value_one：＆＃34; value＆＃34;，value_two：＆＃34; value＆＃34; }进入segment_groups内的序列数组。我的查询如下：

db.messages.update({"segment_groups.segments.group_segment_id": 597268},{$push:{ "segment_groups.segments.$.sequences":{"value_one":"value", "value_two":"value"}}})

尝试此操作时出现错误：

"code" : 16837,
        "errmsg" : "cannot use the part (segment_groups of segment_groups.segments.0.sequences) to traverse the element ({segment_groups: [ { grouping_id: 692335, segments: [ { segment_id: \"test\", group_segment_id: 597268, sequences: [] } ] } ]})"
    enter code here

我已经在这个问题上待了一天，并没有找到任何关于如何解决或如何重组我的收藏的合理建议。我是mongo的新手，在构建时我不了解最佳实践，因此任何使这个更好的解决方案所需的方法都是有价值的。

Answer 1

你遇到的问题是你的模型有两层嵌套数组（segments_groups和segments），Mongo无法弄清楚该数组中哪些项需要更新。

在MongoDB 3.6中，使用arrayFilters / positional filtered operator可以很容易地解决这个问题。在更新路径中，为每个数组指定代表一个特定项的占位符，然后必须添加匹配条件arrayFilters，以帮助MongoDB查找要更新的项目。在你的情况下：

db.messages.update({"_id" : "T6GqWsi9qSxnyGzgC"}, 
    { $push: { "segment_groups.$[sg].segments.$[s].sequences": {"value_one":"value", "value_two":"value"} } }, 
    { arrayFilters: [ { "sg.grouping_id": 692335 }, { "s.group_segment_id": 597268 } ] })

所以$[sg]是一个segment_group，$[s]代表一个细分。

更新时出现Mongo错误：无法使用该部件遍历元素

1 个答案: