This example creates a C scalar UDF named write_mq that writes a message to an external queue. The function calls an MQ access module, identical to the access module a TPump job or other utility might use when processing from a queue.
The SQL is a simple SELECT request that contains nothing in the select list but the scalar UDF and the arguments it expects. When this request is performed, it produces the message, 'Hello World,' which is placed on an MQ queue on the client:
SELECT WriteMQ('queue.manager.1','QUEUE1','CHANNEL1/TCP/ 126.96.36.199', 'Hello World');
The parameters passed are the queue manager (qmgr ), queue name (qnm ), client communication channel (channel), and the message itself (vcmsg), respectively.
The following is the DDL used to create the function.
CREATE FUNCTION write_mq( qmgr VARCHAR(256), qnm VARCHAR(256), channel VARCHAR(256), vcmsg VARCHAR(32000)) RETURNS INTEGER LANGUAGE C NO SQL PARAMETER STYLE SQL EXTERNAL NAME 'F:emruwmq:SI:cmqc:/usr/include/cmqc.h:SL:mqic :SL:mqmcs:SS:emruwmq:/home/rmh/projects/emruwmq/emruwmq.c';