neo4j中的分组查询

cypher语言中的分组与sql略有不同，在cypher中不用显式的写group by分组字段，由解释器自动决定：即未加聚合函数的字段自动决定为分组字段，如：

with [
      {name:'a',sex:'F',country:'CN',age:10},
      {name:'b',sex:'F',country:'CN',age:10},
      {name:'c',sex:'M',country:'CN',age:10},
      {name:'d',sex:'M',country:'US',age:10}
] as p
unwind p as pp
with pp.name as name,pp.sex as sex,pp.country as country,pp.age as age
return sex,country,count(*)

将返回

sex	country	count(*)
"F"	"CN"	2
"M"	"US"	1
"M"	"CN"	1