在 Cypher 中使用除匹配之外的正则表达式 [英] Using regular expressions beyond matching in Cypher

问题描述

我进行以下查询

neo4j-sh (?)$ start n=node(*) where n.name  =~ 'u(.*)' return n; 
==> +-----------------------+
==> | n                     |
==> +-----------------------+
==> | Node[311]{name:"u1"}  |
==> | Node[312]{name:"u2"}  |
==> | Node[313]{name:"u3"}  |
==> | Node[314]{name:"u4"}  | 

我想添加一个userId"属性并将其设置为名称键中的数字.我的意思是我想要

I want to add a "userId" property and set it the number in the name key. I mean I want

==> +-----------------------+
==> | n                     |
==> +-----------------------+
==> | Node[311]{name:"u1", userId:'1'}  |
==> | Node[312]{name:"u2", userId:'2'}  |
==> | Node[313]{name:"u3"},userId:'3'  |
==> | Node[314]{name:"u4"}, userId:'4' | 

现在我需要从 n.name 中去除数字.我怎样才能做到这一点?如何从正则表达式中的 (.*) 中获取值?

Now I need to strip the numbers from n.name. How can I do this? How can I get the value from the (.*) in regex?

推荐答案

你不能在 Cypher 中这样做(据我所知)——regex 只是为了匹配.

You can't do that in Cypher (as far as I know)--regex is just for matching.

如果前面总是只有一个字母，可以取子串:

If it's always just a single letter in front of it, you can take the substring:

start n=node(*) 
set n.userId = substring(n.name, 1)

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