Is it possible to create ksql table from ksql stream?

Question

I'm a new bee to ksql. I'm just playing with read kafka topics to streams and it works great.

Also, trying to create a table from kafka topic and failed. Realized that I need to have a key set in kafka topic which is considered as primary key in ksql table. So I tried creating table from stream instead, but failed too. Query/Script:

CREATE TABLE DETAILS_TABLE AS SELECT SEQ, Server1, ServerId, NumberUri, SERVERID2, SERVER2 FROM details_stream WINDOW TUMBLING (SIZE 1 MINUTES);
Invalid result type. Your SELECT query produces a STREAM. Please use CREATE STREAM AS SELECT statement instead.

Can someone explain if its possible or not? If yes, wher am I going wrong? Thanks.

Answer 1

As Matthias says, you need to specify a (valid) aggregate query.

So this would work:

CREATE TABLE DETAILS_TABLE AS \
SELECT SEQ, Server1, ServerId, NumberUri, SERVERID2, SERVER2, COUNT(*) AS TOTAL \
FROM details_stream WINDOW TUMBLING (SIZE 1 MINUTES) \
GROUP BY SEQ, Server1, ServerId, NumberUri, SERVERID2, SERVER2;

Just as any SQL dialect, if you are doing an aggregation, you have to GROUP BY all of the fields, otherwise it makes no syntactical sense.