问题
Hive's function explode is documented here It is essentially a very practical function that generates many rows from a single one. Its basic version takes a column whose value is an array of values and produces a copy of the same row for each of those values.
I wonder whether such a thing exists in Impala. I haven't been able to find it in the documentation.
回答1:
Impala does not have any function like EXPLODE in hive to read complex data types and generate multiple rows.
Currently through Impala, we can just read the complex data types in Hive generated tables using dot notation like select employee.empid from table1 .
Impala can query complex type columns only from Parquet tables or Parquet partitions within partitioned tables
来源：https://stackoverflow.com/questions/47436977/is-there-a-function-equivalent-to-hives-explode-function-in-apache-impala