Query to obtain indirect relations

[rubenluengas]

I have a "model" with players, teams and stadiums

Players below=> teams
players play in =>stadiums

I have some players that do not below to any teams.

Example:
John is a player of the TEAM A, and play in "central stadium"
Mike is a player that play in "central stadium"
Mike has NO relation with any team.

Can I perform a query that when I ask for the Mike TEAM is show to me that Mike is related with "TEAM A" ? Just try to infere the TEAM

[andrew_bowman]

I'm not entirely sure what you're asking for here.

If you want to get Mike's team, but not wipe out the row if he doesn't belong to a team, use an OPTIONAL MATCH to the team, and you can use coalesce() to provide a default if a null is encountered:

MATCH (m:Player {name:'Mike'})
OPTIONAL MATCH (m)-[:BELONGS_TO]->(t:Team)
RETURN coalesce(t.name, 'NOT ASSIGNED') as teamName

[rubenluengas]

I want to try to do something like the following

John plays for "TEAM A" in the "central stadium" so if Mike plays also in the central stadium Mike should play in the "TEAM A"

[andrew_bowman]

Okay, do you want a query that will set this data for you based on that, or do you want it to not write to the db but return that info at query time?

[rubenluengas]

Not to write. Only in query time

[andrew_bowman]

Okay, something like this maybe? Note that if there are people from multiple teams that play in the same stadium then this will pick one.

MATCH (p:Player {name:'Mike'})
OPTIONAL MATCH (p)-[:BELONGS_TO]->(team)
WITH p, team
MATCH (p)-[:PLAYS_IN*2]-()-[:BELONGS_TO]->(someTeam)
WITH team, collect(DISTINCT someTeam)[0] as fallbackTeam
RETURN coalesce(team.name, fallbackTeam.name, 'UNASSIGNED') as assignedTeam