> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zeotap.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Understand One-to-Many Relationship in NCE

Let’s consider and example to under this concept better. Say, a customer with unique ID (UCID) has multiple phone numbers (personal, work, and family plans). Each phone number is associated with different subscription plans, data usage, and billing details. In this case, the UCID has a one-to-many relationship with the phone numbers and their corresponding details.

Here is how this relationship appears in JSON format, which is how the system receives Non-Customer Entity (NCE) data. By using a Non-Customer Entity source, you can efficiently organize and analyze these relationships to improve personalisation and operational efficiency.

```json JSON theme={null}
{
  "ucid": "123456",
  "subscriptions": [
    {
      "plan_id": "PLAN001",
      "plan_name": "Unlimited Talk & Text",
      "data_limit_gb": 5,
      "price_per_month": 20,
      "status": "Active",
      "propensity_score": 0.85
      
    },
    {
      "plan_id": "PLAN002",
      "plan_name": "Family Plan",
      "data_limit_gb": 50,
      "price_per_month": 60,
      "status": "Inactive",
      "propensity_score": 0.65
      
    },
    {
      "plan_id": "PLAN003",
      "plan_name": "Work Plan",
      "data_limit_gb": 10,
      "price_per_month": 35,
      "status": "Active",
      "propensity_score": 0.92
      
    }
    
  ]
  
```

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