Chapter 7. SQL Remote Design for Adaptive Server Anywhere

SalesRepData - Publication Name rep1 - BEFORE list

rep2 - AFTER list UPDATE Contact

SET contact_key = ’contact1’, name = ’David’, cust_key = ’cust1’

WHERE contact_key = ’contact1’ SalesRepData - Publication Name rep1 - BEFORE list

rep2 - AFTER list UPDATE Customer

SET rep_key = ’rep2’ WHERE cust_key = ’cust1’

The Message Agent scans the log for these tags. Based on this information it can determine which remote users get an INSERT, UPDATE or DELETE.

In this case, the BEFORE list was rep1 and the AFTER list is rep2. If the before and after list values are different, the rows affected by the UPDATE statement have “moved” from one subscriber value to another. This means the Message Agent will send a DELETE to all remote users who subscribed by the value rep1 for the Customer record cust1 and send an INSERT to all remote users who subscribed by the value rep2.

If the BEFORE and AFTER lists are identical, the remote user already has the row and an UPDATE will be sent.

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Sybase DC38133-01-0902-01 manual SalesRepData Publication Name rep1 Before list