time column used by timer

[lec ssmi]

In KeyedProcessFunction, we can register a timer based on EventTime, but in the register method, we don't need to specify the time column. So if the elements of this KeyedStream are not the classes that originally specified timestamp and watermark, can this timer run normally?

[Timo Walther]

Hi,

timestamps and watermarks are attached to every stream record in the
runtime. After assignTimestampsAndWatermarks() extracted them, Flink
handles those attributes internally.

For example, it doesn't matter which class you are emitting in a flatMap
function, the runtime will set the timestamp for all emitted records to
the input timestamp.

Regards,
Timo


On 02.02.20 11:12, lec ssmi wrote:
> In KeyedProcessFunction, we can register a timer based on EventTime, but
> in the register method, we don't need to specify the time column. So if
> the elements of this KeyedStream are not the classes that originally
> specified timestamp and watermark, can this timer run normally?