Hive中的嵌套案例陈述

Question

有没有人知道为什么这段代码不起作用？

create table2 as
select
    *,
    1 as count,
    case
        when a=1 then
            case 
                when tx="A_L" then "L"
                when tx="B_A" then "A"
                when tx="C_E" then "E"
                when tx in ("E_V","D_M","H_O","I_D") then "Other"
                when tx="F_S" then "S"
                when tx="G_L" then "L"
            end 
        when b=1 then 
            case
                when tx="A_L" then "L"
                when tx="B_A" then "A"
                when tx="C_E" then "E"
            end
        else
            case
                when tx="A_L" then "L"
                when tx="B_A" then "A"
                when tx="C_E" then "E"
                when tx in ("D_M","E_V","F_S","H_O","I_D") then "Other"
                when tx="G_L" then "L"
            end
    end as tx1
from table1

或者有更简单的方法吗？我在proc sql语句中编写它并将其推送到Hadoop（因此它需要与HiveQL兼容）。

Answer 1

使用AND或OR子句将嵌套的Case语句组合成一个case语句。这样可以。

Answer 2

而不是测试，这个更具可读性。

concat