Creates a new read session, which may include additional options such as
requested parallelism, projection filters and constraints.
Required. String of the form projects/{project_id}
indicating the project this ReadSession is associated with.
This is the project that will be billed for usage.
Optional. Initial number of streams. If unset or 0, we will
provide a value of streams so as to produce reasonable
throughput. Must be non-negative. The number of streams may be
lower than the requested number, depending on the amount
parallelism that is reasonable for the table and the maximum
amount of parallelism allowed by the system. Streams must be
read starting from offset 0.
