JSON Unnesting

Why JSON Unnesting?

Simplifies Queries: Flatten nested data for easier filtering, aggregations, and joins.
Improves Performance: Avoids expensive JSON path evaluations at query time.
Streamlines Data Modeling: Convert complex structures into relational form at ingestion.

Whether you’re dealing with clickstream data, telemetry logs, or API responses, unnesting simplifies data modeling and enhances query performance.

Enabling JSON Unnesting in StarTree

JSON unnesting can be configured via:

The StarTree Data Portal UI, or
The ingestion config JSON using transformConfigs and unnestConfig.

Examples

Let’s go through a few examples to unnest a JSON Object,

Example 1: Unnesting a JSON Object

Input JSON:

{
  "user": {
    "id": 123,
    "name": "Alice"
  },
  "event": "click"
}

Unnesting Config:

"ingestionConfig": {
    "transformConfigs": [
      {
        "columnName": "user_id",
        "transformFunction": "JSONPATHLONG(user, '$.id')"
      },
      {
        "columnName": "user_name",
        "transformFunction": "JSONPATHSTRING(user, '$.name')"
      }
    ]
}

Resulting Schema:

user_id	user_name	event
123	Alice	click

Example 2: Unnesting an Array into Multiple Rows

Input JSON:

{
  "orderId": "A001",
  "items": [
    { "sku": "X1", "qty": 2 },
    { "sku": "X2", "qty": 1 }
  ]
}

Unnesting Config:

{
 "ingestionConfig": {
   "complexTypeConfig": {
     "delimiter": "_",
      "fieldsToUnnest": ["items"],
      "collectionNotUnnestedToJson": "NON_PRIMITIVE"
   }
 }
}

Resulting Schema:

orderId	items_sku	items_qty
A001	X1	2
A001	X2	1

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Release Notes

Reference

Why JSON Unnesting?

Enabling JSON Unnesting in StarTree

Examples

Example 1: Unnesting a JSON Object

Example 2: Unnesting an Array into Multiple Rows

​Why JSON Unnesting?

​Enabling JSON Unnesting in StarTree

​Examples

​Example 1: Unnesting a JSON Object

​Example 2: Unnesting an Array into Multiple Rows

Why JSON Unnesting?

Enabling JSON Unnesting in StarTree

Examples

Example 1: Unnesting a JSON Object

Example 2: Unnesting an Array into Multiple Rows