Count type of nodes in a list

Neo4j Graph Platform Cypher
, ,
1

Hi,
I have list of nodes with the same label (e.g :Car), there is a property call "type" (e.g SUV, Coupe, Sedan.....) which is used to differenciate the nodes, Now I would like to get the number of different types inside the list (e,g 25 SUVs, 35 Coupes, 40 Sedans). How could I do that?

Thanks,
Oli

2 
match (a:Car)
with distinct a.type as type, count(a) as cnt
return type, cnt order by cnt desc
3

Thanks for your reply. I think the result is what I need. Just one thing is that all my nodes are in a list and I need to get the value based on the list, if you know how to do that?

oli

4

Please let me know what you mean by 'nodes are in a list'. I assume the node has property with list values. Post a sample of that property so that I can suggest an answer.

5 
// suppost I randomly sample the car nodes
with collect(c) as car
// now I have a list called "cars"
// I wish to know the types and their corresponding amount within a list
with distinct a.type as type, count(a) as cnt
return type, cnt order by cnt desc
// The car structure is (c:car {carID, carType})
6 
Try this:
// suppost I randomly sample the car nodes
with collect(c) as car
// now I have a list called "cars"

UNWIND car as car1
WITH car1.type as type, count(distinct car1) as cnt
return type, cnt order by cnt desc
// The car structure is (c:car {carID, carType})
7

up3
up31018×202 1.1 KB

I got this (the list contains 100 samples and 2 or 3 types)

8

Post your Cypher query that produced 100 samples and 2 or 3 types.

9

It works finally, mis-typed, my bad :sweat_smile:
By the way, I would like to ask that if it's possible for us to use uwind with case when to achieve this？

10

Send me the Cypher you used with CASE statement.

11 
with collect(c) as car
unwind car as car1
case car1.type
when "SUC"
Then
// something like x = x + 1
when "Coupe"
Then
// y = y + 1
when "Sedan"
Then
// z = z + 1
end
// or maybe use foreach
foreach(ig in case when car1.type = "SUV") THEN [1] ELSE [] END |  x = x + 1)
foreach(ig in case when car1.type = "Coupe") THEN [1] ELSE [] END |  y = y + 1)
foreach(ig in case when car1.type = "Sedan") THEN [1] ELSE [] END |  z = z + 1)
12

It would be better to count based on type, then sum over the counts:

...
with collect(c) as cars
UNWIND cars as car
WITH car.type as type, count(distinct car) as cnt
WITH CASE WHEN type = 'SUV' THEN cnt ELSE 0 END as suvs, 
  CASE WHEN type = 'Coupe' THEN cnt ELSE 0 END as coupes,
  CASE WHEN type = 'Sedan' THEN cnt ELSE 0 END as sedans
RETURN sum(suvs) as suvs, sum(coupes) as coupes, sum(sedans) as sedans