put (Function)
Function returns the updated map after adding the given key-value pair. If the key already exist in the map the key is updated with the new value.
Syntax
<OBJECT> map:put(<OBJECT> map, <OBJECT|INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> key, <OBJECT|INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> value)
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| map | The map to which the value should be added. | OBJECT | No | Yes | |
| key | The key to be added. | OBJECT INT LONG FLOAT DOUBLE FLOAT BOOL STRING | No | Yes | |
| value | The value to be added. | OBJECT INT LONG FLOAT DOUBLE FLOAT BOOL STRING | No | Yes |
Example 1
map:put(stockDetails , 'IBM' , '200')
In this example, the map:put(stockDetails, 'IBM', '200') function updates the map named stockDetails by adding a new key-value pair to it. The key is 'IBM' and the corresponding value is '200'. The function will return the updated map which includes the new key-value pair.
CREATE STREAM StockInput (symbol string, price float, stockDetails object);
CREATE SINK STREAM UpdatedStockDetails (updatedStockDetails object);
@info(name = 'AddNewStock')
INSERT INTO UpdatedStockDetails
SELECT map:put(stockDetails, symbol, price) AS updatedStockDetails
FROM StockInput;
In this stream worker, the StockInput stream includes an additional attribute stockDetails, which is a map that we will update. The AddNewStock query selects the output of the map:put(stockDetails, symbol, price) function from the StockInput stream.
This function updates the map stockDetails with each incoming event from StockInput by adding or updating a key-value pair to it. The key is the symbol of the stock, and the corresponding value is its price.
The updated map is then inserted into the UpdatedStockDetails stream. This way, the stockDetails map keeps updating with every incoming stock detail from the StockInput stream.
This stream worker assumes that you provide an initial map as an input in the StockInput stream. If you want to start with an empty map, you'll need to use a function that allows creating an empty map or check for null and create an empty map before using map:put().