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extract_json()
Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel
Get a specified element out of a JSON text using a path expression.
Optionally convert the extracted string to a specific type.
The
extract_json()andextractjson()functions are equivalent
Syntax
extract_json(jsonPath, dataSource, type)
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| jsonPath | string |
✔️ | A JSONPath that defines an accessor into the JSON document. |
| dataSource | string |
✔️ | A JSON document. |
| type | string |
An optional type literal. If provided, the extracted value is converted to this type. For example, typeof(long) will convert the extracted value to a long. |
Performance tips
- Apply where-clauses before using
extract_json(). - Consider using a regular expression match with extract instead. This can run very much faster, and is effective if the JSON is produced from a template.
- Use
parse_json()if you need to extract more than one value from the JSON. - Consider having the JSON parsed at ingestion by declaring the type of the column to be dynamic.
Returns
This function performs a JSONPath query into dataSource, which contains a valid JSON string, optionally converting that value to another type depending on the third argument.
Example
let json = '{"name": "John", "age": 30, "city": "New York"}';
print extract_json("$.name", json, typeof(string));
Output
| print_0 |
|---|
| John |