Hi Matt, Nifi does handle other parts of it, just different process group. Regards, Victor
On Mon, Oct 29, 2018 at 12:39 PM Matt Burgess <mattyb...@apache.org> wrote: > Victor, > > Yes, both QDT and GTF would generate something like "SELECT * from > myTable where event_time > X", and QDT will execute it and update X. > So if event_time is always increasing, it will continue to pick up the > same row(s). > > That's a curious use case, maybe NiFi could handle other parts of it > so you wouldn't need to update a single row in an external database > table? > > Regards, > Matt > > On Mon, Oct 29, 2018 at 12:36 PM l vic <lvic4...@gmail.com> wrote: > > > > What if have only one row and update the values in it? Will QDT fetch > updates? > > Thank you, > > Victor > > > > > > On Mon, Oct 29, 2018 at 11:54 AM Matt Burgess <mattyb...@apache.org> > wrote: > >> > >> You can use QueryDatabaseTable (QDT) for this, you'd set your > >> "event_time" column as the "Maximum Value Column(s)" property in the > >> processor. The first time QDT executes, it will fetch all the rows > >> (since it has not seen event_time before), then it will keep track of > >> the largest value of event_time. As new rows are added (with larger > >> event_time values), QDT will only fetch the rows whose event_time is > >> greater than the largest one it's seen. Then it updates its "largest > >> seen value" and so on. > >> > >> GenerateTableFetch (GTF) is another option, it works in a similar > >> fashion, except that it does not fetch the rows itself, instead it > >> generates flow files containing SQL statements that you can send > >> downstream to perhaps ExecuteSQL in order to actually fetch the rows. > >> GTF is often used in place of QDT if you'll be fetching a large number > >> of rows in each statement, as you can distribute the SQL flow files > >> among the nodes in a cluster, to do the fetch in parallel. > >> > >> Regards, > >> Matt > >> > >> On Mon, Oct 29, 2018 at 11:13 AM l vic <lvic4...@gmail.com> wrote: > >> > > >> > Hi, > >> > i have "event_time" field in SQLite database that means epoch time > for triggering of external event. What processor(s) can i use to implement > schedule monitoring/ execution based on change in "event_time" value? > >> > Thanks, >
