Hive: The following columns have types incompatible with the existing columns

Since Hive can't feel compatibility of complicated data structure like struct, so if you intend to change a column of type array<struct<a:int, b:int>> to array<struct<a:int, b:int, c:int>>, it will complains error: "The following columns have types incompatible with the existing columns".

It's easy to depress the above check by setting `set hive.metastore.disallow.incompatible.col.type.changes=false;` and khalas.