# Expand JSON attributes into rows

`json_each` turns the immediate children of a JSON object or array into queryable rows. It is useful when each attribute should become an observation, rather than remaining inside one result value.

```sql
SELECT key, value, type
FROM json_each('{"region":"west","retries":2,"enabled":true}')
ORDER BY key
FORMAT csv;
```

For an object, `key` identifies a field. For an array, it identifies an element position. The `type` column helps distinguish text, numeric, boolean and nested values before interpreting them. A nested object is still one immediate child; use `json_tree` when the task requires descendants too.

Expanding children changes cardinality: one document can produce many rows. Count the expanded attributes separately from the number of original documents. Restrict the keys or types in `WHERE` before aggregating values that should be comparable. Do not sum an attribute merely because its textual representation looks numeric.

For a fixed schema, use `jsonb_to_record` or `jsonb_to_recordset` with declared output types instead of treating every field as a generic attribute. For native arrays, membership queries often need only `has`, without any expansion.

See [JSON functions](https://coordinatordb.com/docs/reference/functions/regular-functions/json-functions) and [array functions](https://coordinatordb.com/docs/reference/functions/regular-functions/array-functions).