在猫鼬模式中嵌套对象数组

Question

I am creating a Student data schema in which a student contains marks of each sem. I want to create an array of sem in which the Sem_Schema must be the ref object. By using the Sem_Schema I want to create the sem Array of Sem_Schema Object. Please help.

var Student_Data_Schema = new mongoose.Schema({
name:{type:String,default:"Rahul Kandiboina", required: true},
reg_no:{type:String,default:"315175711057", required: true},
dob:{type:String,default:"july 3 1998"},
BG:{type:String,default:"o +ve", required: true},
ctg:{type:String,default:"B", required: true},
caste:{type:String,default:"BC", required: true},
EAMCET_Rank:{type:String,default:"29000", required: true},
ECET_Rank:{type:String,default:"123", required: true},
SSC_M:{type:String,default:"9.3", required: true},
Inter_M:{type:String,default:"960", required: true},
DEP_M:{type:String,default:"870", required: true},
BTECH_AGG:{type:String,default:"7.5", required: true},
GRE:{type:String,default:"60", required: true},
GATE:{type:String,default:"120", required: true},
CAT:{type:String,default:"10000", required: true},
TOEFL:{type:String,default:"100", required: true},
E_MAIL:{type:String,default:"rahulkandiboina9@gmail.com", required: 
true},
// Father :{},
// Mother :{},
// Bro :{},
// Sis :{},
Pre_Add :{
            D_no:{type:String},
            Street:{type:String},
            village:{type:String},
            town:{type:String},
            District:{type:String},
            State:{type:String},
            Pin:{type:String}
            },
Per_Add:{
    D_no:{type:String},
    Street:{type:String},
    village:{type:String},
    town:{type:String},
    District:{type:String},
    State:{type:String},
    Pin:{type:String}
},
Marks:{
    CGPA:{type:Number},
    B_LOGS:{type:Number},
    Sem :[Sem_Schema]
}
})



var Sem_Schema =  new mongoose.Schema({
SGPA :{type:String},
CGPA :{type:String},
B_Logs :{type:String},
Sem_Att :{type:String},
T_Sess :{type:String}
})

I want to nest Sem_Schema into Sem array but the error goes like

F:\\Project\\WEB\\NewPro\\NodeJs\\node_modules\\mongoose\\lib\\schema.js:398
throw new TypeError('Invalid value for schema Array path ' + prefix + key + ' '); ^

TypeError: Invalid value for schema Array path Marks.Sem at Schema.add (F:\\Project\\WEB\\NewPro\\NodeJs\\node_modules\\mongoose\\lib\\schema.js:398:13) at Schema.add (F:\\Project\\WEB\\NewPro\\NodeJs\\node_modules\\mongoose\\lib\\schema.js:407:14) at new Schema (F:\\Project\\WEB\\NewPro\\NodeJs\\node_modules\\mongoose\\lib\\schema.js:114:10) at Object. (F:\\Project\\WEB\\NewPro\\NodeJs\\Models\\dept.js:3:27) at Module._compile (internal/modules/cjs/loader.js:688:30) at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10) at Module.load (internal/modules/cjs/loader.js:598:32) at tryModuleLoad (internal/modules/cjs/loader.js:537:12) at Function.Module._load (internal/modules/cjs/loader.js:529:3) at Module.require (internal/modules/cjs/loader.js:636:17) at require (internal/modules/cjs/helpers.js:20:18) at Object. (F:\\Project\\WEB\\NewPro\\NodeJs\\Router\\college.js:3:14) at Module._compile (internal/modules/cjs/loader.js:688:30) at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10) at Module.load (internal/modules/cjs/loader.js:598:32) at tryModuleLoad (internal/modules/cjs/loader.js:537:12)

Answer 1

declare your Sem_Schema before Student_Data_Schema like this. What happens here is when your refer this after your schema it doesn't know what is this Sem_schema is that's what causing this. so change the code to ,

var Sem_Schema =  new mongoose.Schema({
SGPA :{type:String},
CGPA :{type:String},
B_Logs :{type:String},
Sem_Att :{type:String},
T_Sess :{type:String}
})

// after this add the next schema

var Student_Data_Schema = new mongoose.Schema({
name:{type:String,default:"Rahul Kandiboina", required: true},
reg_no:{type:String,default:"315175711057", required: true},
dob:{type:String,default:"july 3 1998"},
BG:{type:String,default:"o +ve", required: true},
ctg:{type:String,default:"B", required: true},
caste:{type:String,default:"BC", required: true},
EAMCET_Rank:{type:String,default:"29000", required: true},
ECET_Rank:{type:String,default:"123", required: true},
SSC_M:{type:String,default:"9.3", required: true},
Inter_M:{type:String,default:"960", required: true},
DEP_M:{type:String,default:"870", required: true},
BTECH_AGG:{type:String,default:"7.5", required: true},
GRE:{type:String,default:"60", required: true},
GATE:{type:String,default:"120", required: true},
CAT:{type:String,default:"10000", required: true},
TOEFL:{type:String,default:"100", required: true},
E_MAIL:{type:String,default:"rahulkandiboina9@gmail.com", required: 
true},
// Father :{},
// Mother :{},
// Bro :{},
// Sis :{},
Pre_Add :{
            D_no:{type:String},
            Street:{type:String},
            village:{type:String},
            town:{type:String},
            District:{type:String},
            State:{type:String},
            Pin:{type:String}
            },
Per_Add:{
    D_no:{type:String},
    Street:{type:String},
    village:{type:String},
    town:{type:String},
    District:{type:String},
    State:{type:String},
    Pin:{type:String}
},
Marks:{
    CGPA:{type:Number},
    B_LOGS:{type:Number},
    Sem :[Sem_Schema]
}
})