OrientDB 在 embeddedlist 列上执行分组

Question

我有以下查询：

SELECT Sub_Type, count(Sub_Type)     
FROM SOME_TABLE  
GROUP BY Sub_Type

Sub_Type 字段类型是字符串的嵌入列表

我得到的结果是：

Blotter_Sub_Type | count
["A"] | 2
["B"] | 3
["C"] | 3
["A","B"] | 1
["B","C"] | 1

但是当我真正想要得到每个值出现的次数时，我的预期结果是：

Blotter_Sub_Type | count
"A" | 3
"B" | 5
"C" | 4

意味着它将单独计算每个值的出现次数

Answer 1

您必须使用 UNWIND 和子查询：

SELECT Sub_Type, count(Sub_Type) FROM (
   SELECT Sub_Type FROM SOME_TABLE UNWIND Sub_Type
) GROUP BY Sub_Type

OrientDB perform a group by on embeddedlist column