OptionalchunkRows asked for per request. A server that returns fewer than asked is fine: the next request simply starts where that response ended.
Filters to send with every request, keyed by column id.
OptionalmaxUpper bound on the rows returned. No request asks for rows past it, so it also bounds the load put on the server.
OptionalsignalCancels the remaining requests. Passed through to every getRows call.
Sorts to send with every request, primary first.
Options for fetchAllRows.