Usage

The MQCreateVtiReceive() function 3creates a table_name bound to a queue specified by service_name, 3using the quality of service policy defined in policy_name. 3Selecting from this table returns all the available messages in 3the queue and also removes the messages from the queue. If no messages 3are available to be returned, the no rows are returned. An insert 3into the bound table puts messages in the queue.

The table created has the following schema and uses the "informix".mq access method: 3

create table table_name (
3       msg lvarchar(maxMessage),
3       correlid varchar(24),
3       topic varchar(40),
3       qname varchar(48),
3       msgid varchar(12),
3       msgformat varchar(8));
3               using "informix".mq (SERVICE = service_name,
3                                    POLICY = policy_name,
3                                    ACCESS = "RECEIVE");

The mapping between a table bound to a queue requires translation 3of operation. Actions on specific columns within the table are translated 3into specific operations within the queue, as outlined here:

3
• An insert operation maps the following columns to the MQ manager: 3 3
  3
  • msg. The text that will be inserted onto 3the queue
  3
  • correlid. The key recognized by queue 3manager to get messages from the queue
3
• A select operation maps the following columns to the MQ manager: 3 3
  3
  • msg. The message is removed from the queue.
  3
  • correlid. Within the WHERE clause, is 3the value passed to the queue manager to qualify messages (the correlation 3identifier). The only operator that should be used when qualifying 3is equals (=).

The following table describes how the arguments for the MQCreateVtiReceive() function 3are interpreted. 3