Hi Andy, Thanks.
When the driver requests X rows, C* will load the whole partition (All rows) before reply to driver ? Thanls. 2018-04-24 18:11 GMT+02:00 Andy Tolbert <andrew.tolb...@datastax.com>: > Hi Ahmed, > > The java driver docs do a good job explaining how the driver uses paging, > including providing a sequence diagram that describes the flow of the > process: https://docs.datastax.com/en/developer/ > java-driver/3.5/manual/paging/ > > The driver requests X rows (5000 by default, controlled via > QueryOptions.setFetchSize > <https://docs.datastax.com/en/drivers/java/3.5/com/datastax/driver/core/QueryOptions.html#setFetchSize-int->) > at a time. When C* replies, it returns a 'paging state' id which > identifies where in the result set (partition and clustering key) to > continue retrieving the next set of rows. When you continue iterating over > the result set in the java driver and hit the end of the current page, it > will send another request to C* using that paging state to get the next set > of rows. > > Thanks, > Andy > > On Tue, Apr 24, 2018 at 9:49 AM, Ahmed Eljami <ahmed.elj...@gmail.com> > wrote: > >> Hello, >> >> Can someone explain me how paging is implemented ? >> >> according to the doc of datastax, the goal being to avoid loading much >> results in memory. >> >> Does it mean that the whole partition is not upload to heap memory? >> >> >> C* version: 2.1 >> >> Java Driver version: 3.0 >> >> Best regards >> >> > -- Cordialement; Ahmed ELJAMI