How to create a text index for nested fields with the same name

php editor Strawberry will introduce how to create a text index in a nested field with the same name. In databases, we often encounter situations where we need to search and query in nested fields. However, creating a text index becomes complicated when there are multiple nested fields with the same name. This article will explain in detail how to deal with this problem and provide you with a solution. Next, we'll walk you through the step-by-step process to easily create text indexes for nested fields with the same name.

Question content

I am trying to create a compound text index on 2 nested fields with the same name. The reason I'm trying to do this is so I can perform a full text search using mongo on both fields.

Data structure example

{
    "createdat": "2023-01-20t18:39:45.551z",
    "id": "63cadff13fc409d0b026f219",
    "userid": "63c13a9ba4c921b78e7d1a3a",
    "question": {
        "statement": "what is the atomic number of potassium?",
        "fileurl": "http://localhost:4000/media/90152d8363424e688ad6e9505194a818.jpg",
        "mediatype": 2
    },
    "answer": {
        "statement": "19"
    }
}

As you can see from the example, question and answer have the same nested field statement. I'm trying to create a text index for question and answer statements

What I try to do

    textsearchindexmodel := mongo.indexmodel{
        keys: bson.d{
            {value: "question.statement", key: "text"},
            {value: "answer.statement", key: "text"},
        },
        options: options.index().setname("textsearchindex"),
    }

This did not work and produced this error:

Failed to create index for flashcard collection:....caused by :: 
The field 'text' appears multiple times in the index key pattern

• Is there a way to do this?
• Is my approach correct for what I want to achieve?

p.s: If you are not familiar with go, you can also upload it on mongodb as the mapping to mongodb go driver is very simple

Workaround

Please note that a collection can have at most one text index .

If you know this and want to create a text index covering "question.statement" and "answer.statement", then this works.

Your mistake is the index specification: bson .d represents a document, an ordered list of attributes (name-value pairs). This is part of bson.e where bson. e is:

type e struct {
    key   string
    value interface{}
}

key is the name of the attribute, value is the value of the attribute. So you turned it upside down and it should be:

textSearchIndexModel := mongo.IndexModel{
    Keys: bson.D{
        {Key: "question.statement", Value: "text"},
        {Key: "answer.statement", Value: "text"},
    },
    Options: options.Index().SetName("textSearchIndex"),
}

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