get (Function)
Function returns the value corresponding to the given key from the map.
Syntax
<OBJECT|INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> map:get(<OBJECT> map, <INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> key)
<OBJECT|INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> map:get(<OBJECT> map, <INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> key, <OBJECT|INT|LONG|FLOAT|DOUBLE|FLOAT|BOOL|STRING> default.value)
Query Parameters
| Name | Description | Default Value | Possible Data Types | Optional | Dynamic |
|---|---|---|---|---|---|
| map | The map from where the value should be obtained. | OBJECT | No | Yes | |
| key | The key to fetch the value. | INT LONG FLOAT DOUBLE FLOAT BOOL STRING | No | Yes | |
| default.value | The value to be returned if the map does not have the key. | OBJECT INT LONG FLOAT DOUBLE FLOAT BOOL STRING | Yes | Yes |
Example 1
map:get(companyMap, 1)
The map:get(companyMap, 1) function retrieves the value associated with the key 1 from companyMap. If companyMap includes the key 1 and its value is ABC, the function returns ABC. If the key is not present in companyMap, the function returns null.
Example 2
map:get(companyMap, 2)
The map:get(companyMap, 2) function retrieves the value associated with the key 2 from companyMap. If companyMap includes the key 2, it returns the corresponding value. If the key 2 does not exist in companyMap or doesn't have an associated value, the function returns null.
Example 3
map:get(companyMap, 2, 'two')
The map:get(companyMap, 2, 'two') function retrieves the value associated with the key 2 from companyMap. If companyMap includes the key 2, it returns the corresponding value. If the key 2 does not exist in companyMap or doesn't have an associated value, the function returns the provided default value 'two'.
Example 4
CREATE STREAM InputStream (companyMap object, searchKey int);
CREATE SINK STREAM OutputStream (companyValue object);
@info(name = 'CompanyMapLookup')
INSERT INTO OutputStream
SELECT map:get(companyMap, searchKey) AS companyValue
FROM InputStream;
In this stream worker, the CompanyMapLookup query processes events from the InputStream, each event comprising a companyMap and a searchKey. The query applies the map:get(companyMap, searchKey) function to each event in InputStream to retrieve the value associated with searchKey from companyMap. The resultant value is then inserted into the OutputStream for each processed event.