flink sql 计算列不支持comment

[silence-2]

Flink版本：1.11.1

 

官网文档中定义如下：

<computed_column_definition>:

  column_name AS computed_column_expression [COMMENT column_comment]

我看到官方文档中计算列是可以指定column_comment的，但我尝试了一下发现会报错

 

使用方式和报错信息如下：

create table t1(

       data_time STRING,

       row1_time AS to_timestamp(data_time) COMMENT 'test'

       WATERMARK FOR row1_time AS row1_time - INTERVAL '5' SECOND

) with(...)

 

org.apache.flink.sql.parser.impl.ParseException: Encountered "COMMENT" at
line 1, column 74.

Was expecting one of:

    "FILTER" ...

    "OVER" ...

    "WITHIN" ...

    ")" ...

    "," ...

    "." ...

    "NOT" ...

    "IN" ...

    "<" ...

    "<=" ...

    ">" ...

    ">=" ...

    "=" ...

    "<>" ...

    "!=" ...

    "BETWEEN" ...

    "LIKE" ...

    "SIMILAR" ...

    "+" ...

    "-" ...

    "*" ...

    "/" ...

    "%" ...

    "||" ...

    "AND" ...

    "OR" ...

    "IS" ...

    "MEMBER" ...

    "SUBMULTISET" ...

    "CONTAINS" ...

    "OVERLAPS" ...

    "EQUALS" ...

    "PRECEDES" ...

    "SUCCEEDS" ...

    "IMMEDIATELY" ...

    "MULTISET" ...

    "[" ...

    "FORMAT" ...

    "IGNORE" ...

    "RESPECT" ...

   

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.generateParseException(F
linkSqlParserImpl.java:36086)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.jj_consume_token(FlinkSq
lParserImpl.java:35900)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreateTable(FlinkSqlP
arserImpl.java:5271)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreateExtended(FlinkS
qlParserImpl.java:6269)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreate(FlinkSqlParser
Impl.java:19047)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlStmt(FlinkSqlParserIm
pl.java:3308)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlStmtList(FlinkSqlPars
erImpl.java:2775)

       at
org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.parseSqlStmtList(FlinkSq
lParserImpl.java:252)

       at
org.apache.calcite.sql.parser.SqlParser.parseStmtList(SqlParser.java:201)

[Leonard Xu]

Hi, sllence

这是个bug, 看起来是支持计算列时漏掉了comment的解析，我开了个issue去修复[1].

祝好
Leonard

[1] https://issues.apache.org/jira/browse/FLINK-19092 <https://issues.apache.org/jira/browse/FLINK-19092>

> 在 2020年8月29日，13:37，<[hidden email]> <[hidden email]> 写道：
>
> Flink版本：1.11.1
>
>
>
> 官网文档中定义如下：
>
> <computed_column_definition>:
>
>  column_name AS computed_column_expression [COMMENT column_comment]
>
> 我看到官方文档中计算列是可以指定column_comment的，但我尝试了一下发现会报错
>
>
>
> 使用方式和报错信息如下：
>
> create table t1(
>
>       data_time STRING,
>
>       row1_time AS to_timestamp(data_time) COMMENT 'test'
>
>       WATERMARK FOR row1_time AS row1_time - INTERVAL '5' SECOND
>
> ) with(...)
>
>
>
> org.apache.flink.sql.parser.impl.ParseException: Encountered "COMMENT" at
> line 1, column 74.
>
> Was expecting one of:
>
>    "FILTER" ...
>
>    "OVER" ...
>
>    "WITHIN" ...
>
>    ")" ...
>
>    "," ...
>
>    "." ...
>
>    "NOT" ...
>
>    "IN" ...
>
>    "<" ...
>
>    "<=" ...
>
>    ">" ...
>
>    ">=" ...
>
>    "=" ...
>
>    "<>" ...
>
>    "!=" ...
>
>    "BETWEEN" ...
>
>    "LIKE" ...
>
>    "SIMILAR" ...
>
>    "+" ...
>
>    "-" ...
>
>    "*" ...
>
>    "/" ...
>
>    "%" ...
>
>    "||" ...
>
>    "AND" ...
>
>    "OR" ...
>
>    "IS" ...
>
>    "MEMBER" ...
>
>    "SUBMULTISET" ...
>
>    "CONTAINS" ...
>
>    "OVERLAPS" ...
>
>    "EQUALS" ...
>
>    "PRECEDES" ...
>
>    "SUCCEEDS" ...
>
>    "IMMEDIATELY" ...
>
>    "MULTISET" ...
>
>    "[" ...
>
>    "FORMAT" ...
>
>    "IGNORE" ...
>
>    "RESPECT" ...
>
>
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.generateParseException(F
> linkSqlParserImpl.java:36086)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.jj_consume_token(FlinkSq
> lParserImpl.java:35900)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreateTable(FlinkSqlP
> arserImpl.java:5271)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreateExtended(FlinkS
> qlParserImpl.java:6269)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlCreate(FlinkSqlParser
> Impl.java:19047)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlStmt(FlinkSqlParserIm
> pl.java:3308)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.SqlStmtList(FlinkSqlPars
> erImpl.java:2775)
>
>       at
> org.apache.flink.sql.parser.impl.FlinkSqlParserImpl.parseSqlStmtList(FlinkSq
> lParserImpl.java:252)
>
>       at
> org.apache.calcite.sql.parser.SqlParser.parseStmtList(SqlParser.java:201)
>