+1 for voting. Best, Jingsong
On Thu, Apr 6, 2023 at 4:52 PM yuxia <luoyu...@alumni.sjtu.edu.cn> wrote: > > Hi everyone. > > If there are no other questions or concerns for the FLIP[1], I'd like to > start the vote next Monday (4.10). > > [1] > https://cwiki.apache.org/confluence/display/FLINK/FLIP-302%3A+Support+TRUNCATE+TABLE+statement > > Best regards, > Yuxia > > ----- 原始邮件 ----- > 发件人: "yuxia" <luoyu...@alumni.sjtu.edu.cn> > 收件人: "dev" <dev@flink.apache.org> > 发送时间: 星期五, 2023年 3 月 24日 上午 11:27:42 > 主题: Re: [DISCUSS] FLIP-302: Support TRUNCATE TABLE statement > > Thanks all for your feedback. > > @Shammon FY > My gut feeling is that the end user shouldn't care about whether it'll delete > direcotry or move to Trash directory with the TRUNCATE TABLE statement. They > only need to know it will delete all rows from a table. > To me, I think delete directory or move to trash is more likely to be a > behavior of external storage level instead of SQL statement level. In Hive, > if user configure Trash, it will then move files to trash for DROP statment. > Also, hardly did I see such usage with TRUNCATE TABLE statement in other > engines. What's more, to support it, we have to extend the TRUNCATE TABLE > synax which won't then compliant with SQL standard. I really don't want to do > that and I believe it'll make user confused if we do so. > > @Hang > `TRUNCATE TABLE` is meant to delete all rows of a base table. So, it makes no > sense that table source implements it. > If user use TRUNCATE TABLE statement to truncate a table, the planner will > only try to > find the DynamicTableSink for the corresponding table. > > @Ran Tao > 1: Thanks for you reminder. I said it won't support view in the FLIP, but > forget to said temporary table is also not supported. Now, I add this part to > this FLIP. > > 2: Yes, I also considered to incldue it in this FLIP before. But as far as I > see, I haven't seen much usage of truncate table with partition. It's not as > useful as truncate table. So, I tend to keep this FLIP simple in here without > supporting truncate table with partition. > Also, seems for `truncate table with partition`, differnet engines may have > differernt syntax; > Hive[1]/Spark[2] use the following syntax: > TRUNCATE TABLE table_name [PARTITION partition_spec] > > SqlServer[3] use the follwoing syntax: > TRUNCATE TABLE { database_name.schema_name.table_name | > schema_name.table_name | table_name } [ WITH ( PARTITIONS ( { > <partition_number_expression> | <range> } > So, I'm tend to be cautious about it. > > But I'm open to this. If there's any feedback or strong requirement, I don't > mind to add it in this FLIP. > If we do need it in some day, I can propose it in a new FLIP. It won't break > the current design. > > As for concrete syntax in the FLIP, I think the current one is the concrete > syntax, we don't allow TABLE keyword to be optional. > > 3: Thanks for your reminder, I have updadted the FLIP for this. > > > [1]https://cwiki.apache.org/confluence/display/hive/languagemanual+ddl#LanguageManualDDL-TruncateTable > [2]https://spark.apache.org/docs/3.0.0-preview/sql-ref-syntax-ddl-truncate-table.html > [3]https://learn.microsoft.com/en-us/sql/t-sql/statements/truncate-table-transact-sql?view=sql-server-ver16 > > > > Best regards, > Yuxia > > ----- 原始邮件 ----- > 发件人: "Ran Tao" <chucheng...@gmail.com> > 收件人: "dev" <dev@flink.apache.org> > 发送时间: 星期四, 2023年 3 月 23日 下午 6:28:17 > 主题: Re: [DISCUSS] FLIP-302: Support TRUNCATE TABLE statement > > Hi, yuxia. > > Thanks for starting the discussion. > I think it's a nice improvement to support TRUNCATE TABLE statement because > many other mature engines supports it. > > I have some questions. > 1. because table has different types, whether we will support view or > temporary tables? > > 2. some other engines such as spark and hive support TRUNCATE TABLE with > partition. whether we will support？ > btw, i think you need give the TRUNCATE TABLE concrete syntax in the FLIP > because some engines has different syntaxes. > for example, hive allow TRUNCATE TABLE be TRUNCATE [TABLE] which means > TABLE keyword can be optional. > > 3. The Proposed Changes try to use SqlToOperationConverter and run in > TableEnvironmentImpl#executeInternal. > I think it's out of date, the community is refactoring the conversion logic > from SqlNode to operation[1] and executions in TableEnvironmentImpl[2]. > I suggest you can use new way to support it. > > [1] https://issues.apache.org/jira/browse/FLINK-31464 > [2] https://issues.apache.org/jira/browse/FLINK-31368 > > Best Regards, > Ran Tao > https://github.com/chucheng92 > > > yuxia <luoyu...@alumni.sjtu.edu.cn> 于2023年3月22日周三 21:13写道： > > > Hi, devs. > > > > I'd like to start a discussion about FLIP-302: Support TRUNCATE TABLE > > statement [1]. > > > > The TRUNCATE TABLE statement is a SQL command that allows users to quickly > > and efficiently delete all rows from a table without dropping the table > > itself. This statement is commonly used in data warehouse, where large data > > sets are frequently loaded and unloaded from tables. > > So, this FLIP is meant to support TRUNCATE TABLE statement. M ore exactly, > > this FLIP will bring Flink the TRUNCATE TABLE syntax and an interface with > > which the coresponding connectors can implement their own logic for > > truncating table. > > > > Looking forwards to your feedback. > > > > [1]: [ > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-302%3A+Support+TRUNCATE+TABLE+statement > > | > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-302%3A+Support+TRUNCATE+TABLE+statement > > ] > > > > > > Best regards, > > Yuxia > >
