Drop column in Impala

Question

我想在Impala中删除整个列'index'(列名和值):

customer_idxxx56

删除带有ALTER TABLE mytab DROP COLUMN col的列只会改变元数据，底层数据保持不变。这意味着虽然数据是完整的，但您得到了列移位。

唯一的解决方案是备份，删除和重新创建表。

create table DBName.Tablename_tmp as select case_id,    customer_id from DBName.Tablename; -- just backup table with new structure.
drop table DBName.Tablename;
create table DBName.Tablename as select * from DBName.Tablename_stg;