(c:Customer)-[:ordered]->(p:Product)-[:category]->(:Category)
Now, say that there are 2:
c-[:ordered]->(:Product { name: "pants", quantity: 10})
c-[:ordered]->(:Product { name: "shirt", quantity: 5})
Now, say that if I only want to cross the category relationship if the
p.quantity > 6
In the most basic way, I would do:
(c:Customer)-[:ordered]->(p:Product)-[:category]->(cat:Category)
WHERE p.quantity > 6
However, I figured that maybe neo4j would (non-optimally) traverse the
entire path _then_ filter where on top of the path.
So what I did was:
MATCH (c:Customer)-[:ordered]->(p:Product)
WHERE p.quantity > 6
WITH p
MATCH p-[:category]->(cat:Category)
This, I figured, would then allow neo4j to cross out to all the product
nodes, as I would need them anyway in order to filter out the ones which
have a quantity of less than 6.
Now... finally to my question.
The following URL:
http://docs.neo4j.org/chunked/stable/query-match.html
states that:
WHERE defines the MATCH patterns in more detail. The predicates are part of
the pattern description, not a filter applied after the matching is done.
So, my question is, if the predicates (specifically p.quantity > 6) are
part of the pattern description, and _not_ applied _after_ matching
(therefore applied before or during), then cutting the query with the WITHs
would be a moot point
So, I would think that
(c:Customer)-[:ordered]->(p:Product)-[:category]->(cat:Category)
WHERE p.quantity > 6
would be sufficient, , as neo4j _would not_ actually traverse to cat, since
it would apply the filter during the match process.
However, in practice, I notice that using WITH is actually faster. Is there
any possible reason for this?
It may be necessary for me to show my query exactly, I also have the
profile data for the query, which I am currently analyzing
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