如何使用mongodb中的golang从json数组中获取嵌套值

Question

I am having the below json

I want to extract the value of particular Data from Requirement array based on Id. If "Data" = "String123" it should display the "Data" as ["WED"].

I tried this code

but I am getting all values irrespective of Id.

Answer 1

If I get you right you have one record in "clOfferMaster" collection and you're trying to fetch data from nested collection "Eligibility". That's probably not a typical way to work with data.

What if you restructure your data as follows:

[ 
    {
        "ComponentId" : "SessionDayCheck",
        "ConfigData" : [ 
            "WED"
        ]
    }, 
    {
        "ComponentId" : "TransDayCheck",
        "ConfigData" : [ 
            "WED", 
            "THU"
        ]
    }, 
    {
        "ComponentId" : "SessionTransCheck",
        "ConfigData" : ""
    }
]

It that case you can do the following query

c := session.DB("offerengine2").C("clOfferMaster")

var result struct {
    ConfigData []string "ConfigData"
}
err = c.Find(bson.M{"ComponentId": "SessionDayCheck"}).One(&result)
if err != nil {
    log.Fatal(err)
}

fmt.Println("Result:", result)
// Result: {[WED]}