LET表达式可用来定义变量并在表达式中立即使用这些变量。使用LET表达式可以提升代码可读性，简化复杂表达式。

<let value expression> ::=
 "LET" <let variable definition list> "IN" <value expression> "END"

<let variable definition list> ::=
  <let variable definition> [ { "," <let variable definition> }... ]

<let variable definition> ::= <binding variable> "=" <value expression>

示例图集

以下示例根据该图集运行：

在空图集中运行以下语句创建示例图集：

INSERT (p1:Paper {_id:'P1', title:'Efficient Graph Search', score:6}),
       (p2:Paper {_id:'P2', title:'Optimizing Queries', score:9}),
       (p3:Paper {_id:'P3', title:'Path Patterns', score:7}),
       (p1)-[:Cites]->(p2),
       (p2)-[:Cites]->(p3)

示例

RETURN LET x = 2, y = 1 IN x^2+y END AS result

结果：

MATCH (n:Paper)
RETURN n.title, LET plus = 1 IN n.score + plus END AS newScore

结果：