ObjRelationPojo Table a record 

public class YpObjRelationPojo implements Serializable {
@Id

private String id; // ' Primary key id'

@Field("sourceid")

private String sourceId; // object id

@Field("targetid")

private String targetId; // object id

@Field("caseId")

private String caseId; // case id

@Transient // Configure transparent properties 

private int source; // ' Starting point of relationship No database 

@Transient

private int target; // ' The end of the relationship No database 

@Transient

private String color;

@Transient

private String relation; // ' Relationship name '

@Field("relation_type")

@DBRef

private YpRelationTypePojo relation_type;

@Field("create_time")

private Date create_Time; // ' Creation time '

omitted set,get Method

@DBRef Used to associate objects

{
"_id" : ObjectId("54a24e8a25600d768a4e13ac"),
"sourceid" : "54a20a6dd9d886078991aa98",
"targetid" : "54a209dfd9d886078991aa95",
"caseId" : "100",
"relation_type" : {
"$ref" : "relationtype",
"$id" : ObjectId("54a21b0ad9d886078991aa9e")
}
}

If you need to find out in this record relation_type, View the associated objects

We need to use the point notation

Id by relation_type The record of the table id

ObjectId objectId = new ObjectId(Id);

Query query1=Query.query(Criteria.where("relation_type.$id").is(objectId));

List<YpObjRelationPojo> r=mongoTemplate.find(query1, YpObjRelationPojo.class, "YpObjRelationPojo");

After finding out , Delete this field

Update update=new Update();

update.unset("relation_type");

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