Hey, I have considered the Temporal Table Joins, but as far as I know from the docs, it is only currently supported in the Blink Planner and does not currently support event time join, which is why I was trying to find a different solution. Or has anything changed or is my understanding incorrect ??
Best Regards, Dom. wt., 21 sty 2020 o 11:08 Piotr Nowojski <pi...@ververica.com> napisał(a): > Hi, > > You have basically a motivating example between Temporal Table Joins [1]. > Please take a look at them. > > Piotrek > > [1] > https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/streaming/temporal_tables.html > < > https://ci.apache.org/projects/flink/flink-docs-stable/dev/table/streaming/temporal_tables.html > > > > > On 20 Jan 2020, at 17:02, Dominik Wosiński <wos...@gmail.com> wrote: > > > > Hello, > > I wanted to ask whether the idea and the general concept that I have is > > correct or if there is anything better in Flink to use. > > > > Say, I that I have 3 different streams : > > > > - currency_codes, which has the name of the currency. It has the > > following fields (*currency_iso_code, tst, currency_name)* > > - exchange_rate, which is a rarely changing stream that has data bout > > exchange rates for different currencies. It has the following > > fields (*currency_iso_code, > > tst, rate*) > > - fares, which represents taxi fares. It has the following fields > > (*currency_iso_code, > > tst, price*) > > > > Generally, let's assume that this is the simple system that allows > drivers > > to charge clients in different currencies, but in the end, we want to > have > > all calculations in USD, but we want to have the *name* of the original > > currency. > > > > The current idea that I have is that since *currency_codes* have the > names > > of the currencies and it does not change frequently (say It will change > > once a month tops) we should use this as a *BroadcastState *to be able to > > join it with *exchange_rate*. After that, when we have the name of the > > foreign currency and the exchange rate, we can use a LATERAL TABLE join > to > > join it with Fares. > > > > The question is, whether my assumptions are correct and if there is any > > better idea to solve this problem? > > > > Thanks in advance, > > Best Regards, > > Dom. > >
