delay advice - Huge resultset
Thanks  Akina - your message helped me get on the right track and sort this out:


  Copy this result to (temporary) table with additional autoincrement field (with the name rownum, for example, autoincrement field will (must) be PRIMARY KEY, so it will be filled with values automatically), then expose the data from this table and select first/next chunks by this field values (WHERE rownum BETWEEN 50*@chunknum-49 AND 50*@chunknum).


I ended up creating a new table using the previous resultset with the rownum autoincrement that you suggested