Chapter 7. SQL Remote Design for AdaptiveSer verAnywhere
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’
TheMessage Agent scans the log for these tags. Basedon this
informationit can determine which remote users get an INSERT,
UPDATEor DELETE.
Inthis case, the BEFORE list was rep1 and the AFTER list is rep2. Ifthe
beforeand after list values are different, the rows affected by the
UPDATEstatement have “moved” from one subscriber value to another.
Thismeans the Message Agent will send a DELETE to all remote users
whosubscribed by the value rep1 for the Customer record cust1 and
sendan INSERT to all remote users who subscribed by the value rep2.
Ifthe BEFORE and AFTER lists are identical, the remote user already
hasthe row and an UPDATE will be sent.
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