IBM InfoSphere CDC - "Supplemental logging not enabled for OBJECT"

For any read-only DB connections (to Oracle) InfoSphere CDC does additional checking to see if the supplemental logging for the all the tables that are relevant to the subscriptions. This is an initial ONE TIME sanity check for any read-only connections when we change from REFRESH mode to MIRROR mode.

InfoSphere CDC has the system parameter called "read_only_check_supplemental_logging" to enable or disable this ONE TIME sanity check because some customers can enable the supplemental logging ONLY for few selected columns. For such customers, this system parameter helps to by-pass this sanity check. After the instance goes to MIRROR mode, CDC does not look back this system parameter. So, it is harmless to keep this system parameter around OR one can choose to unset this parameter after CDC goes to the MIRROR mode. When this sanity check is disabled, it is assumed by InfoSphere CDC that the source database is providing the supplemental logging for all the columns in the tables that are relevant to the subscriptions.

Comments

  1. Unknown11 October 2011 at 04:21

    Thanks Srini, Can you please explain other such parameters.

    ReplyDelete

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