createFromJSON (Function)
Function returns the map created by pairing the keys with their corresponding values given in the JSON string.
Syntax
<OBJECT> map:createFromJSON(<STRING> json.string)
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| json.string | JSON as a string, which is used to create the map. | STRING | No | Yes |
Example 1
map:createFromJSON('{"symbol" : "IBM", "price" : 200, "volume" : 100}')
This function creates a map from a JSON string. The provided JSON string {"symbol" : "IBM", "price" : 200, "volume" : 100} is converted into a map with keys symbol, price, and volume mapped to their corresponding values IBM, 200, and 100.
Example 2
CREATE STREAM InputStream (jsonString string);
CREATE SINK STREAM OutputStream (mapOutput object);
@info(name = 'CreateMapFromJSON')
INSERT INTO OutputStream
SELECT map:createFromJSON(jsonString) AS mapOutput
FROM InputStream;
In this example, a stream worker is created that uses the map:createFromJSON function to convert each jsonString event in the InputStream into a map. This map is then output as mapOutput in the OutputStream.
This example allows you to create maps dynamically from JSON strings coming in through a stream, which can be a powerful tool when dealing with JSON data in real-time streaming scenarios.