我一直在玩 OrientDB sql 查询以获得一个结果集,该结果集不仅包含顶点,还包含它们之间存在的内部边。
查询可以表示为:
project
相关的顶点(不包括项目本身)以及结果中包含的顶点之间的所有边 这是我实现它的方式,但我认为这不是正确的方法。
select expand($union) let $vertices = ( select from ( traverse both() from (select from V where label = 'project') ) skip 1 ), $edges = ( select from ( select from E where @rid in ( select bothE() from ( select from ( traverse both() from (select from V where label = 'project') ) skip 1 ) ) ) where out in ( select from ( traverse both() from (select from V where label = 'project') ) skip 1 ) and in in ( select from ( traverse both() from (select from V where label = 'project') ) skip 1 ) ), $union = unionall($vertices, $edges)
和预期的结果:
此解决方案的问题:
select from V where label = 'project'
也被执行了几次。 有没有更好的方法来解决这个用例?
谢谢。
最佳答案
试试这个查询:
select expand($c)
let $a=(traverse both(),bothE() from (select from V where label="project")),
$b=(traverse bothE() from (select from V where label="project")),
$c=difference($a,$b)
关于sql - OrientDB 如何在一个查询中获取顶点及其边的结果集,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34064874/