基本语法：

ALTER TABLE name RENAME TO new_name
ALTER TABLE name ADD COLUMNS (col_spec[, col_spec ...])
ALTER TABLE name DROP [COLUMN] column_name
ALTER TABLE name CHANGE column_name new_name new_type
ALTER TABLE name REPLACE COLUMNS (col_spec[, col_spec ...])

refer:https://www.yiibai.com/hive/hive_alter_table.html

自己实验：

1. alter table d_extra.dm_usr_mxdai_risk_analysis add columns(test1 int, test2 int); ------works

desc d_extra.dm_usr_mxdai_risk_analysis;

可以看出新字段已经添加成功

1.1.alter table d_extra.dm_usr_mxdai_risk_analysisaddcolumn test1 int; ------doesn't work

2. alter table d_extra.dm_usr_mxdai_risk_analysis drop column test1; -----doesn't work

报错：

Error: Error while compiling statement: FAILED: ParseException line 1:52 mismatched input 'column' expecting PARTITION near 'drop' in drop partition statement (state=42000,code=40000)

是不是只能drop partition 而不能drop column？？

3. alter table d_extra.dm_usr_mxdai_risk_analysis change test1 risk_1_138 string; ------works