zoucao created FLINK-26401:
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             Summary: improve the compatibility for hive catalogView
                 Key: FLINK-26401
                 URL: https://issues.apache.org/jira/browse/FLINK-26401
             Project: Flink
          Issue Type: Improvement
          Components: Connectors / Hive
            Reporter: zoucao


For now, many reserved keywords were kept for FlinkSQL[1], and some of them are 
different from other bigdata systems, like spark[2], hive[3]. In this context, 
users may be affected by the compatibility of various systems. 
For example, the keyword 'DATE' is marked as reserved by Flink and Hive, but 
not in spark. If the hive view is defined as 
{code:java}
select a, b, date from hive_tb where date = '2022-02-28' 
{code}
It will work well in spark, but in flink, the SqlParserException about ' SQL 
parse failed. Encountered "date at line xxx, column xxx '. IIUC, If we do 
nothing to improve the compatibility, users must change the query about the 
hive view to 
{code:java}
select a, b, `date` from hive_tb where date = '2022-02-28' 
{code}
, to make Flink work.
I think we can add a converter to surround reserved keywords with backticks 
before parsing.

[1] 
https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/sql/overview/
[2] 
https://spark.apache.org/docs/3.2.1/sql-ref-ansi-compliance.html#sql-keywords
[3] 
https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-Keywords,Non-reservedKeywordsandReservedKeywords



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