Usage

The MQCreateVtiRead() function creates 3a table bound to a queue specified by service_name, 3using the quality of service policy defined in policy_name. 3Selecting from the table created by this function returns all the 3committed messages in the queue, but does not remove the messages 3from the queue. If no messages are available to be returned, the 3SELECT statement returns no rows. An insert to the bound table puts 3a message into 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 = "READ");

The mapping for 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 inserts the following into the mapped table 3column: 3 3
  3
  • msg. The message text that will be inserted 3onto the queue.
  3
  • correlid. The message will be sent with 3the specified correlation identifier.
3
• A select operation maps these in the following way to a WMQ 3queue: 3 3
  3
  • msg. The message is retrieved from the 3queue
  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 MQCreateVtiRead() function 3are interpreted. 3