Iterate batch query records and join into a single message

Hello there, I'm trying to generate a daily summary report using batch query. When querying with group by on some tag, a record set will be fetched. Is it possible to iterate the record set and fill each row data into a single message template? So that I can send email using this summary message. If it's not possible, can you suggest the best practice for such intention? Thanks very much!

Start by investigating the batch query and grouped record-set behavior described in the issue, including how results could feed a message template and email. Done would require confirming whether row iteration and message joining are supported, or documenting an agreed best-practice approach.

Written by the indexing model from the issue text.