Cypher で次のクエリの出力を理解しようとしています。
start n=node:node_auto_index(name="root_node")
match n-[:SC]->c, b<-[:CB]-c-[:CB]->b1
where (b.days_in_number - b1.days_in_number <= 7) AND (b.days_in_number > b1.days_in_number)
and c.name = "C16659"
with distinct n,c, b, b1
match n-[:SC]->c-[:CB]->b-[:CT]->i1, n-[:SC]->c-[:CB]->b1-[:CT]->i2
with b.name as bname,b1.name as b1name,i1.name as i1name,i2.name as i2name
return bname,b1name,i1name,i2name
order by bname,b1name,i1name,i2name;
3680 行を返します
start n=node:node_auto_index(name="root_node")
match n-[:SC]->c, b<-[:CB]-c-[:CB]->b1
where (b.days_in_number - b1.days_in_number <= 7) AND (b.days_in_number > b1.days_in_number)
and c.name = "C16659"
with distinct n,c, b, b1
match b-[:CT]->i1, b1-[:CT]->i2
with b.name as bname,b1.name as b1name,i1.name as i1name,i2.name as i2name
return bname,b1name,i1name,i2name
order by bname,b1name,i1name,i2name;
184行を返します
クエリ 1 はデカルトを行っているようですが、その理由がわかりません。誰でも説明できますか?
c-[:CB]->b は 1:n の関係です。
アップデート:
次のクエリを実行すると、正しい 184 の結果が得られます。
start n=node:node_auto_index(name="root_node")
match n-[:SC]->c, b<-[:CB]-c-[:CB]->b1
where (b.days_in_number - b1.days_in_number <= 7) AND (b.days_in_number > b1.days_in_number)
and c.name = "C16659"
with distinct n,c, b, b1
match c-[:CB]->b-[:CT]->i1, c-[:CB]->b1-[:CT]->i2
with n.name as nname,c.name as cname, b.name as bname,b1.name as b1name,i1.name as i1name,i2.name as i2name
return nname,cname,bname,b1name,i1name,i2name
order by nname,cname,bname,b1name,i1name,i2name;
これは、 n を元に戻すとデカルトにつながることを示唆しています。
n-[:SC]->c は 1:1 の関係です。なぜこうなった?