StreamSQL Multi-row Functions

Multi-row functions are used for handling multi-row data.

UNNEST - Unnest Function

Syntax: unnest(array)
Description: Expands an array into multiple rows.
Incremental Calculation: Not Supported

Example 1 - Expand Simple Array:

SELECT unnest(tags) as tag FROM events

Input Data:

{
  "id": 1,
  "tags": ["a", "b", "c"]
}

Output Result:

{"tag": "a"}
{"tag": "b"}
{"tag": "c"}

Example 2 - Expand Object Array:

SELECT unnest(items) FROM orders

Input Data:

{
  "order_id": "O001",
  "items": [
    {"product": "apple", "price": 1.5},
    {"product": "banana", "price": 0.8}
  ]
}

Output Result:

{"product": "apple", "price": 1.5}
{"product": "banana", "price": 0.8}

📚 Related Documentation

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• SQL Reference - View complete SQL syntax reference