If I Change the watermark prefix, will it impact already watermarked messages?

[dmaze531]

Problem we are trying to solve: We have vendors that use their own instances of ServiceNow. Sometimes they will send emails to our instance that originated from their instances of ServiceNow (With their instances watermark). We are seeing collisions whereby their watermarks are the same as a watermark on our instances. Thus the wrong records are being updated in our instance.   I'm thinking I can simply change the watermark prefix in our instance from "MSG" to something more unique such as "ZZZ". Then when we receive an email from our vendors (that prefix with MSG), there will never be a watermark match unless the email was generated from our instance (desired).     If I change the prefix in our instance, will that affect any of the outstanding messages and/or cause any problems? (: if the prefix is changed, does it affect only future emails or does it retro affect previously sent emails)   thoughts?

[Chuck Tomasi · Accepted solution]

Hi Daniel,

The short answer to your question is, no, it won't impact existing watermarks. They are stored in the sys_watermark table so incoming messages sent out a week before you changed the prefix will still work (and are still at risk for what you mentioned above.)

Thanks for the use case. I'll bring that to our developers attention.

[dmaze531]

Thanks ctomasi this is very helpful. Love your pod-cast. You've taught me a ton!

[Pradeep Sharma]

Hi Daniel,

Agree with Chuck, it shouldn't impact your existing watermarks.

You may also find the below blog helpful.

Append a watermark to the email subject

[dmaze531]

Thanks Pradeep.   This is most helpful. I see you take the time to answer many questions. We really appreciate it.