Thanks Sergey for driving this FLIP, it's a great addition to materialized table!
Since it coincided with China's National Day holiday and everyone is still on vacation, we couldn't reply promptly. I haven't fully reviewed all the content in the FLIP yet, but there's an important issue on the ALTER statement: Unlike a regular CREATE TABLE, Materialized Table derives its schema from the defined query, columns are generated based on the query (and, similar to a materialized view, the underlying data for these columns is tightly coupled to the query definition). Therefore, we cannot simply interpret the effect of an single `ALTER MATERIALIZED TABLE ADD New_Column` statement. Supporting this likely requires accompanying column default value，and raises compatibility concerns regarding historical data, that is a complex topic we previously discussed offline during the design process of FLIP-492. Also, once Ron is back in the office, he may give a more detailed comment. Best, Lincoln Lee Sergey Nuyanzin <[email protected]> 于2025年10月2日周四 20:15写道： > Thank you Ramin > > In case there is no more feedback/objections > I would start voting thread next week > > On Thu, Sep 25, 2025 at 10:43 AM Ramin Gharib <[email protected]> > wrote: > > > > Hi Sergey, > > Thanks for driving this! This sounds good to me! +1 > > > > Cheers, > > > > Ramin > > > > On Wed, Sep 24, 2025 at 2:14 PM Sergey Nuyanzin <[email protected]> > wrote: > > > > > Hi everyone, > > > I'd like to start a discussion of FLIP-550 > > > Add similar support for CREATE/ALTER operations for MATERIALIZED > > > TABLEs as for TABLEs [1]. > > > > > > This FLIP is another step towards making tables and materialized > > > tables more consistent. There was already one improvement in that > > > direction like FLIP-542 [2] to add DISTRIBUTION and SHOW MATERIALIZED > > > TABLES support. However there were several more things noticed > > > comparing behavior for CREATE and ALTER operations. For instance right > > > now for materialized tables it is impossible to set anything but table > > > constraint while for tables (CREATE TABLE AS) it is possible to > > > provide schema definition since FLIP-463 [3], also ALTER operations > > > for TABLE is a way more mature than for MATERIALIZED TABLE. This FLIP > > > is about to decrease the difference by enabling more similar features > > > for materialized tables. > > > > > > Introducing schema definition support for materialized tables will > > > provide users with greater control and flexibility and also will unify > > > usage of tables and materialized tables. > > > > > > [1] > > > > https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=387648095 > > > > > > [2] > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-542%3A+Make+materialized+table+DDL+consistent+with+regular+tables > > > > > > [3] > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-463%3A+Schema+Definition+in+CREATE+TABLE+AS+Statement > > > > > > -- > > > Best regards, > > > Sergey > > > > > > > -- > Best regards, > Sergey >
