如何正确使用配置单元变量替换

Question

在蜂巢中使用变量替换时，遇到一些错误，但是需要您的帮助。

我的代码：

set hievar:b='on t1.id=t2.id where t2.id is null';
select * from t_old as t1 full outer join t_new as t2 ${b};

当我在蜂巢壳中运行此代码时，它给我一些关于${b}的错误。

我也尝试这样做：

set hivevar:c='select * from t_old as t1 full outer join t_new as t2 on t1.id=t2.id where t2.id is null';
${c};

它给了我同样的错误。

Answer 1

修复hivevar命名空间名称（在您的代码中为hievar）并删除引号，因为引号也按原样在Hive中传递。

示例：

set hivevar:b=where 1=1; --without quotes
select 1 ${hivevar:b}; --you can do without hivevar: as in your example

结果：

OK
1
Time taken: 0.129 seconds, Fetched: 1 row(s)

第二个示例：

hive> set hivevar:c=select 1 where 1=1;
hive> ${c};
OK
1
Time taken: 0.491 seconds, Fetched: 1 row(s)