hive table new field, modify field comment

(1) create test table:

use mart_flow_test;

create table if not exists mart_flow_test.detail_flow_test

(

union_id string comment ‘device unique id’

) comment ‘test table’

partitioned by (

partition_date string comment ‘log generation date’

) stored as orc;

(2) new field: use mart_flow_test;

alter table detail_flow_test add columns(original_union_id string);

(3) modification comment: use mart_flow_test;

alter table detail_flow_conversion_base_raw change column original_union_id original_union_id string COMMENT’ original device unique id ‘;