Parameters, value
Collection operation can aggregate a column of nodes, edges, paths, property values or schemas into an array in the original order, as long as it is a column of elements, it can be converted into an array by collect().
Syntax:
- format: collect(
<column>) - parameters: (see list below)
- value: ARRAY
| Name | Category | Specification | Description |
|---|---|---|---|
<column> |
NODE，EDGE，PATH，ATTR，ARRAY，TABLE | / | The column to be aggregated |
<column>'s value for each category of <column>:
| Category | value |
|---|---|
| NODE | NODE's UUID in the column |
| EDGE | EDGE's UUID in the column |
| PATH | ROW INDEX（starting from 0）in the column |
| ATTR | ATTR's value in the column |
| ARRAY | ARRAY'S value in the column |
| TABLE | Value of the array transformed from the table in the column |
ATTR
Example: find 10 nodes and collect their schema
find().nodes([1,2,3,4,5,6,7,8,9,10]) as n
return collect(n.@)
NODE
Example: find 10 @product nodes, collect their UUID
find().nodes({@product}) as n
limit 10
return collect(n)
EDGE
Example: find 10 @transfer edges, collect their UUID
find().edges({@transfer}) as e
limit 10
return collect(e)
PATH
Example: find 10 shortest paths from Card CA001 within 2 steps, list the paths by the destination card's balances by descending order, and collect the column number of the paths.
n({_id == "CA001"}).e({@transfer})[2].n(as n).limit(10) as p
order by n.balance desc
return collect(p)
Analysis: the column number of the paths in the stream starts from 0,
ARRAY
Example: find paths from Card CA001 within 3 steps, count the number of the nodes of each path, then collect these nodes
n({_id == "CA001"}).e()[3].n() as p
with pnodes(p) as a
return collect(a)