neo4j unwind

1.将列表转换为行

UNWIND [1, 2, 3, NULL ] AS x
RETURN x, 'val' AS y

2.返回元素唯一的行

WITH [1, 1, 2, 2] AS coll
UNWIND coll AS x
WITH DISTINCT x
RETURN collect(x) AS setOfVals

3.列表相加

WITH [1, 2] AS a,[3, 4] AS b
UNWIND (a + b) AS x
RETURN x

4.拆解list

WITH [[1, 2],[3, 4], 5] AS nested
UNWIND nested AS x
UNWIND x AS y
RETURN y

5.Using UNWIND with an empty list

UNWIND [] AS empty
RETURN empty, 'literal_that_is_not_returned'

6.Using UNWIND with an expression that is not a list

UNWIND NULL AS x
RETURN x, 'some_literal'

7.Creating nodes from a list parameter

参考文献:
https://neo4j.com/docs/developer-manual/3.4/cypher/clauses/unwind/