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# JSON\_REPLACE

## Syntax

```bnf
JSON_REPLACE(json_doc, path, val[, path, val] ...)
```

## Description

Replaces existing values in a JSON document, returning the result, or `NULL` if any of the arguments are `NULL`.

An error will occur if the JSON document is invalid, the path is invalid or if the path contains a `*` or `**` wildcard.

Paths and values are evaluated from left to right, with the result from the earlier evaluation being used as the value for the next.

JSON\_REPLACE can only update data, while [JSON\_INSERT](/docs/server/reference/sql-functions/special-functions/json-functions/json_insert.md) can only insert. [JSON\_SET](/docs/server/reference/sql-functions/special-functions/json-functions/json_set.md) can update or insert data.

## Examples

```sql
SELECT JSON_REPLACE('{ "A": 1, "B": [2, 3]}', '$.B[1]', 4);
+-----------------------------------------------------+
| JSON_REPLACE('{ "A": 1, "B": [2, 3]}', '$.B[1]', 4) |
+-----------------------------------------------------+
| { "A": 1, "B": [2, 4]}                              |
+-----------------------------------------------------+
```

## See Also

* [JSON video tutorial](https://www.youtube.com/watch?v=sLE7jPETp8g) covering JSON\_REPLACE.

<sub>*This page is licensed: CC BY-SA / Gnu FDL*</sub>

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