In this case why do you need to start on the relationship? Can you start with student + relationship instead?
Can you explain in English what you’re trying to ask of be database? Eve On Thu, Apr 12, 2018 at 10:00 AM Marwa Elabri <marwaela...@gmail.com> wrote: > I have two kind of query > the first one I start from a node such as > match (n:student) > optional math (n)-[R:takes]-(n2:course) > return n, n2 > > The second kind of request: I have to start (point) from a relationship > such as: > match ()-[R:takes]-() > optional match ()-[R:takes]-(n:student) > optional match (n:student)-[R:takes]-(p:course) > return n,p > > but when I make this kind of query specially if I point to a relationship > it takes a looooot of time :( so can I find another solution how to improve > this type of query (with optional much) > > thank for your help > > > Le jeudi 12 avril 2018 14:03:47 UTC+2, eve.freema a écrit : > >> Without a query it’s hard to help you on this... >> >> Often, I tell people to start with a match of what you know exists, and >> then do an optional match for what you’re not sure exists, like: >> >> match (p:Person) // we want to get all Person nodes >> optional match (p)-[:FOLLOWS]->(maybe:Person) >> return p.name, maybe.name >> >> This way, you give the engine some help with the starting point. Does >> this help? >> >> Eve >> > On Thu, Apr 12, 2018 at 3:42 AM Marwa Elabri <marwa...@gmail.com> wrote: >> > Hello >>> >>> please are there another clause that replace optional match in cypher >>> query language >>> because I want to get null value from my neo4j database but when I use >>> *optional >>> mach* with a huge database the request execution takes a lot of time >>> ???? >>> >>> Thank you in advance >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Neo4j" group. >>> >> To unsubscribe from this group and stop receiving emails from it, send an >>> email to neo4j+un...@googlegroups.com. >> >> >>> For more options, visit https://groups.google.com/d/optout. >>> >> -- > You received this message because you are subscribed to the Google Groups > "Neo4j" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to neo4j+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to neo4j+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
