isEmpty (Function)
Function checks if the map is empty.
Syntax
<BOOL> map:isEmpty(<OBJECT> map)
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| map | The map the need to be checked whether it's empty or not. | OBJECT | No | Yes |
Example 1
map:isEmpty(stockDetails)
The map:isEmpty(stockDetails) function evaluates whether the stockDetails map is empty. If the map is empty (i.e., it contains no key-value pairs), the function returns true. If the map contains one or more key-value pairs, then it returns false.
Example 2
CREATE STREAM InputStream (stockDetails object);
CREATE SINK STREAM OutputStream (isEmpty bool);
@info(name = 'CheckEmptyMap')
INSERT INTO OutputStream
SELECT map:isEmpty(stockDetails) AS isEmpty
FROM InputStream;
In this stream worker, the CheckEmptyMap query processes events from the InputStream, with each event comprising a stockDetails map. The query applies the map:isEmpty(stockDetails) function to each event in InputStream to determine if stockDetails is empty. The resultant boolean value (true if empty, false otherwise) is then inserted into the OutputStream for each processed event.