[Exim] assigning variable or adding custom entry to log

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Hello,

I am new to exim, and I have been reading the FAQ, but could not find an
answer.

I want to update a user's record in my database whenever a new mail for
this user arrives.
I do this by using an Oracle stored function:
ORA_TIMESTAMP = SELECT
update_Account('${quote_oracle:$domain}','${quote_oracle:$local_part}')
FROM DUAL

When running exim in debug mode I can use
deliver_domain:
debug_print = ${lookup oracle{ORA_TIMESTAMP}}
driver = appendfile
directory = ${lookup oracle{ORA_MAILDIR}{$value}}
delivery_date_add
envelope_to_add
return_path_add
create_directory
maildir_format
mode = 0600
mode_fail_narrower = false

This works fine, but I want to start exim in normal, non debug, mode.
How could I achieve this?
Any assignment to a dummy variable, writing to the log file, or anything
that just evaluates the lookup would be fine.

Thanks for your help.

Chris


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