Profiling

Profiling a query

This query returns the movies that "Clint Eastwood" acted in but did not direct:

MATCH (p:Person)-[:ACTED_IN]->(m:Movie)
WHERE p.name = 'Clint Eastwood'
AND NOT exists {(p)-[:DIRECTED]->(m)}
RETURN m.title

You can profile the query to see the performance of the query by adding PROFILE to the beginning of the query.

PROFILE MATCH (p:Person)-[:ACTED_IN]->(m:Movie)
WHERE p.name = 'Clint Eastwood'
AND NOT exists {(p)-[:DIRECTED]->(m)}
RETURN m.title

The results breakdown the performance of the query into the components of the query.

Review the results. Based on the db hits, which part of the query do you think is the most expensive?

Solution

The correct answer is (p)-[:DIRECTED]→(m). This step has the highest number of db hits.

You may see a different number of db hits if you have made updates to the database.