Inbuilt Functions

Following are the supported inbuilt functions of Siddhi

coalesce

< int|long|float|double|string|bool|object > coalesce (<int|long|float|double|string|bool|object >  arg1, <int|long|float|double|string|bool|object > arg2,.., <int|long|float|double|string|bool|object > argN)

• Extension Type: Function 
• Description: Returns the value of the first non null input parameter.
• Parameters: This function accepts one or more parameters, and they all have to be the same type of, any one of the available types.
• Return Type: Return type will be the first input parameter's type.
• Examples: coalesce('123', null, '789') returns '123'. coalesce(null, 76, 567) returns 76. coalesce(null, null, null) returns null. 

convert

< int|long|float|double|string|bool > convert (<int|long|float|double|string|bool>  toBeConverted, <string> convertedTo)

• Extension Type: Function 
• Description: Converts the first input parameter according to the convertedTo parameter. 
• Parameter: toBeConverted : To be converted parameter with type other than object.
• Parameter: convertedTo : A string constant parameter expressing the everted to type using one of the following strings values: 'int', 'long', 'float', 'double', 'string', 'bool'.
• Return Type: Return type will be type specified by the convertedTo parameter.
• Examples: convert('123', 'double') returns 123.0. convert(45.9, 'int') returns 46. convert(true, 'string') returns 'true'. 

instanceOfBoolean

< bool > instanceOfBoolean (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of Boolean or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of Boolean and false otherwise.
• Examples: instanceOfBoolean(123) returns false. instanceOfBoolean(true) returns true. instanceOfBoolean(false) returns true. 

instanceOfDouble

< bool > instanceOfDouble (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of Double or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of Double and false otherwise.
• Examples: instanceOfDouble(123) returns false. instanceOfDouble(56.45) returns true. instanceOfDouble(false) returns false. 

instanceOfFloat

< bool > instanceOfFloat (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of Float or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of Float and false otherwise.
• Examples: instanceOfFloat(123) returns false. instanceOfFloat(56.45) returns false. instanceOfFloat(56.45f) returns true. 

instanceOfInteger

< bool > instanceOfInteger (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of Integer or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of Integer and false otherwise.
• Examples: instanceOfInteger(123) returns true. instanceOfInteger(56.45) returns false. instanceOfInteger(56.45f) returns false. 

instanceOfLong

< bool > instanceOfLong (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of Long or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of Long and false otherwise.
• Examples: instanceOfLong(123) returns false. instanceOfLong(5667l) returns true. instanceOfLong(56.67) returns false. 

instanceOfString

< bool > instanceOfString (<int|long|float|double|string|bool|object>  arg)

• Extension Type: Function 
• Description: Checks if the parameter is an instance of String or not. 
• Parameter: arg : The parameter to be checked.
• Return Type: Returns bool, true if the parameter is an instance of String and false otherwise.
• Examples: instanceOfString('test') returns true. instanceOfString('5667') returns true. instanceOfString(56.67) returns false. 

UUID

< string > UUID ( )

• Extension Type: Function 
• Description: Generate a UUID. 
• Return Type: Returns a UUID string.
• Examples: UUID() returns a34eec40-32c2-44fe-8075-7f4fde2e2dd8. 

E.g. Converting room number to string and introducing message ID to each event

from TempStream 
select convert(roomNo, 'string') as roomNo, temp, UUID() as messageID
insert into RoomTempStream;