SQL: "bothE" function returns number of edges instead of array of edges

[gramian]

ArcadeDB Version:

ArcadeDB Server v24.5.1-SNAPSHOT (build 7872d1acb3616c2866613dabcb7d899322bb3348/1715204385992/main)

OS and JDK Version:

Running on Mac OS X 12.7.4 - OpenJDK 64-Bit Server VM 17.0.11 (Homebrew)

Expected behavior

[{"@cat":"e","@type":"E","@rid":"#25:0","@in":"#1:0","@out":"#1:0"},{"@cat":"e","@type":"E","@rid":"#25:0","@in":"#1:0","@out":"#1:0"}]

Actual behavior

2

Steps to reproduce

CREATE VERTEX TYPE V;
CREATE EDGE TYPE E;
INSERT INTO V;
CREATE EDGE E FROM (SELECT FROM V) TO (SELECT FROM V);
SELECT bothE() FROM V;

[gramian]

The problem is probably here: https://github.com/ArcadeData/arcadedb/blob/main/engine/src/main/java/com/arcadedb/graph/GraphEngine.java#L438 .

[gramian]

@lvca this is weird:

Changing in https://github.com/ArcadeData/arcadedb/blob/main/engine/src/main/java/com/arcadedb/graph/GraphEngine.java#L438 :

return result;

to:

return () -> result;

seems to make it work, but I do not understand why, as for vertices (see getVertices in the same file) it works correctly without the () ->.

[lvca]

The issue is here:

arcadedb/engine/src/main/java/com/arcadedb/serializer/JsonSerializer.java

Line 107 in 4281a1c

if (useCollectionSizeForEdges && value.iterator().next() instanceof Edge)

. The serializer for studio put edge count every time a collection of edges is present.

From studio if you want to see the result in a table use this SELECT expand( bothE() ) FROM V.

With HTTP/JSON API, the recommended serializer used is "graph" that also uses this settings, so the result would still be 2.

[gramian]

OK, but why do inE and outE work as expected? Also I confirm that bothE works in console.

[lvca]

The reason is that bothE returns a collection. I think it was introduced to avoid serializing vertices with thousands of edges. But in your case you're expressly asking for them, so it should return the edges, not the counter.