Unable to retrieve the values from the database using Mule - stored-procedures

Question

I am trying to pass multiple query parameters through browser as
http://localhost:8081/test?SourceQueue=mqinput&PayloadMsgId=11004a90Test0001-3
My flow is as follows,
I am setting the query params to the payload using set payload transformer and then passing those values to the stored procedure. But I am not able to retrieve the values from the database. The payload is null after the database connector.
My config xml for the flow is as follows:
<http:listener config-ref="HTTP_Listener_Configuration" path="/test"
doc:name="HTTP"/>
<set-payload value="SourceQueue=#[message.inboundProperties.'http.query.params'.SourceQueue],PayloadMsgId=#[message.inboundProperties.'http.query.params'.PayloadMsgId]" doc:name="Set Payload"/>
<logger message="#[payload]----------------before db" level="INFO" doc:name="Logger"/>
<db:stored-procedure config-ref="Generic_Database_Configuration" doc:name="Database">
<db:parameterized-query><![CDATA[{CALL E_Enquiry(:SourceQueue1,:PayloadMsgId1)}]]></db:parameterized-query>
<db:in-param name="PayloadMsgId1" type="VARCHAR" value="#[payload.SourceQueue]"/>
<db:in-param name="SourceQueue1" type="VARCHAR" value="#[payload.PayloadMsgId]"/>
</db:stored-procedure>
<logger message="#[payload]----output" level="INFO" doc:name="Logger"/>
My stored procedure is as follows:
CREATE OR REPLACE PROCEDURE E_Enquiry
(IN SourceQueue1 VARCHAR(30) DEFAULT NULL,
IN PayloadMsgId1 VARCHAR(100) DEFAULT NULL)
LANGUAGE SQL
DYNAMIC RESULT SETS 1
BEGIN
DECLARE C1 CURSOR WITH RETURN TO CLIENT FOR
select PayloadMsgId,ExceptionId,EventSource,E_Message.InterfaceId,
CreationTime,SourceProtocol,ErrorMessage,Severity,InterfaceName
from E_Message,E_Config
where (SourceQueue=SourceQueue1 and PayloadMsgId=PayloadMsgId1);
open c1;
END;

Answer 1

Your expression :-
<set-payload value="SourceQueue=#[message.inboundProperties.'http.query.params'.SourceQueue],PayloadMsgId=#[message.inboundProperties.'http.query.params'.PayloadMsgId]" doc:name="Set Payload"/>
is not correct and you cannot achieve this by setting it into payload as the payload is a String format for now and not an Object.
The ideal solution will be using variables like the following :-
<set-variable variableName="SourceQueuevar" value="#[message.inboundProperties.'http.query.params'.SourceQueue]" doc:name="Set SourceQueuevar"/>
<set-variable variableName="PayloadMsgIdvar" value="#[message.inboundProperties.'http.query.params'.PayloadMsgId]" doc:name="Set PayloadMsgIdvar"/>
Once this is set, you can easily use it anywhere, in you SQL or logger in the following expression like :- #[flowVars.SourceQueuevar] #[flowVars.PayloadMsgIdvar]

Answer 2

FlowVars are an opction, however you could also create a map easily using the following notation:
<set-payload value="#[['SourceQueue':message.inboundProperties.'http.query.params'.SourceQueue,'PayloadMsgId':message.inboundProperties.'http.query.params'.PayloadMsgId]]" doc:name="Set Payload"/>
In this way you could access to the payload as an object (because it is a map). You can access to the payload value with an expression like this:
#[payload.SourceQueue]
or
#[payload.PayloadMsgId]