Schema evolution allows adding columns at any position in the Parquet file. In DDL, the column is added at the end.
ALTER FOREIGN TABLE table nos_table ADD DeptNo;
If schema evolution is disabled, the ALTER FOREIGN TABLE query returns an error.
Select Columns from NOS Table
SELECT EmpID, EmpName, City, DeptNo FROM nos_table;
Result:
EmpID EmpName City DeptNo ----- ------- -------- ------- 65784 John Austin 1759 69824 Robert Atlanta 6294 48392 Frank Columbus 2197 72985 Colin Phoenix 4372 34862 Brandon Hartford 7863