Longest Path with condition

[rinaldo_bonazzo]

Hi,

I need to find the longest path between 2 nodes with the relationship HAS_INVOICE 

MATCH p=(f:Company)-[r:HAS_INVOICE*1..10]->(t:Company)
RETURN p;

this query is working fine.

Now I need only the relationship with invoiceState property with value  DUE or OVERDUE 

MATCH p=(f:Company)-[r:HAS_INVOICE*1..10]->(t:Company)
WHERE NOT (f)-[:HAS_INVOICE {invoiceState = 'PAID'}]->(t)
RETURN p;

Error 

Invalid input '[': expected "+" or "-" (line 2, column 15 (offset: 70))
"WHERE NOT (f)-[:HAS_INVOICE {invoiceState = 'PAID'}]->(t)"
               ^

This query is working fine but I'm not able to retrieve the longestpath

MATCH p=(f:Company)-[r:HAS_INVOICE]->(t:Company) 
WHERE 
r.invoiceState in ['DUE', 'OVERDUE']
RETURN p;

Thanks for your help 

Rinaldo 

[Cobra]

Hi @rinaldo_bonazzo 😄

You should use a predicate function

MATCH p=(f:Company)-[:HAS_INVOICE*1..10]->(t:Company) 
WHERE all(r IN relationships(p) WHERE r.invoiceState in ['DUE', 'OVERDUE'])
RETURN p;

Regards,
Cobra

[glilienfield]

The error is a result of the equal sign. The correct syntax is the following, which will restrict to a relationship the that property value. 

[:HAS_INVOICE{invoiceState: ‘Paid’}]

you can find the longest path by sorting on the path length and returning the longest. Add the following after your ‘RETURN p’ statement:

ORDER BY length(p) DESC

LIMIT 1

the above solution assumes there is only one longest path, or you just one of the longest at random if there are more than one. I can provide a different solution when there could be multiple, but it seems that should not occur in your case. 

[rinaldo_bonazzo]

Thanks @glilienfield I expect to retrive the path greater than 3 hops