JavaScript Extension

define function <function name>[<language name>] return <return type> {

   <operation of the function>

• function name: The name of the function.
• language name: The language of the script. In this scenario, it should be JavaScript.
• return type: The return type of the function (int, long, float, double, string, bool or object).
• operation of the function: The logic of the function.

define function concatFunction[JavaScript] return string {

   var str1 = data[0];

   var str2 = data[1];

   var responce = str1 + str2

   return responce;

};

The above function concatenates two strings and returns the output. The input parameters are automatically input as arrays, and they can be accessed as data[1] and data[0].

A stream can be defined as follows.

define stream TempStream(deviceID long, roomNo int, temp double);

The eval script defined above can be used in this stream as follows.

from TempStream

select concatFunction(roomNo,deviceID) as id, temp  

insert into DeviceTempStream;