Hello all， Spark 2.4.0 was released last month. I noticed that Spark 2.4 “Add a lot of new built-in functions, including higher-order functions, to deal with complex data types easier.”[1] I wonder if it's necessary for Flink to add higher-order functions to enhance it's ability.
By the way, I found that if we wants to enhance the functionality of Flink sql, we often need to modify Calcite. It may be a little inconvenient，so may be we can extend Calcite core parser in Flink to deal with some non-standard SQL syntax, as mentioned in Flink SQL DDL Design[2]. Look forward to your feedback. Best, Wen-hui Tang [1] https://issues.apache.org/jira/browse/SPARK-23899 [2] https://docs.google.com/document/d/1TTP-GCC8wSsibJaSUyFZ_5NBAHYEB1FVmPpP7RgDGBA/edit# Winifred-wenhui Tang
