Neo4j：如何在给定日期范围内按中间日期查询

Question

Neo4J TimeTree is an efficient way of modelling time in a graph. However, I'm interested in how best to model/query for an object with a defined start and end time.

For instance, a ticket might be validFrom and validTo given dates, which may be separated by many days. A user may have many tickets.

For a given date, what is the most efficient way of querying for valid tickets?

When entering the data, I suppose I could create lots of validOn relationships between a ticket and the intermediate days between the start and end, but this seems inefficient. Can anyone think of a better way of querying the data?

I can start from a user and find all tickets for that user whose validFrom is <= and validTo is >= the date. However, what happens if I need to start from a date? Ie match all tickets that are valid on a given date?

Answer 1

You only link the ticket to the validFrom and validTo dates with dedicated relationships.

For any given day, you query backwards for tickets that have their :START relationship before that date but the :END relationship after that date, something like this:

MATCH path = (t:Ticket)-[:START]->(before:Day)-[:NEXT*0..30]->(day:Day {date:{date}})
WHERE (t)-[:END]->(:Day)<-[:NEXT*1..30]-(day)
RETURN t