Function count()
calculates the number of rows of a data column, namely the column length. Only one row from the data stream will be kept after this function is called, and all the rest rows will be abandoned.
Arguments:
- Any Value <any>
Returns:
- Column length <number>
ATTR
Example: deduplicate the elements in an array, count the number of the elements after deduplication
uncollect [1,2,4,5,2,1,3] as a
with distinct(a) as b
return count(b)
Node
Example: find @device
nodes, count the number of them
find().nodes({@device}) as n
return count(n)
Edge
Example: find @view
edges, count the number of it
find().edges({@view}) as e
return count(e)
Path
Example: find the shortest paths from Card CA001 to CA002 within 5 steps, count the number of the paths
n({_id == "CA001"}).e()[*:5].n({_id == "CA002"}) as p
return count(p)