How To Increase The Maximum Size Of DCNs From 1.8KB (default) To 1.8 MB
Last updated on JULY 25, 2017
Applies to:JDBC - Version 126.96.36.199 and later
Information in this document applies to any platform.
The problem is noticed with the maximum size of notifications (Database Change Notifications - DCNs).
Oracle sends a list of rowids for every row that has been modified in a transaction.
But, when the number of updated rows is more than 100, Oracle does not send all rowids updated; instead it just sends an alert stating all the rows in the table have been modified (ALL_ROWS).
The reason for this is that the maximum size of notifications for DCNs is set at 1800 bytes (1.8 KB) by default.
Every rowid alert is about 180 bytes in size. So 100 rowid alerts fill the entire 1800 byte limit and the next (101st) alert causes Oracle to send a wrong notification.
Is it possible to increase the limit to 1.8MB ?
Sign In with your My Oracle Support account
Don't have a My Oracle Support account? Click to get started
My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms