Cypher MATCH on a time-series type silently returns no rows (SQL sees the samples), while the docs list Cypher as a time-series query language #10440

A Cypher MATCH on a time-series type matches nothing. With two samples in a TIMESERIES type Ev, SQL SELECT count(*) FROM Ev returns 2, while Cypher MATCH (e:Ev) RETURN count(e) returns 0 and MATCH (e:Ev) RETURN e returns no rows. Nothing warns that the label belongs to a type Cypher cannot scan, so a query over time-series data just reports that there is none.

The time-series concepts page lists Cypher among the query languages for time-series data: "SQL, PromQL, Cypher, Gremlin, GraphQL, MongoDB QL" (timeseries.adoc L1424-L1425). I only tested Cypher, not Gremlin, GraphQL or MongoDB QL.

I found this while writing the Cypher version of a velocity check, which counts events per account per minute, for a blog post. It now buckets edge timestamps instead and says that Cypher does not read time-series types.

Repro

Server: arcadedata/arcadedb:latest, version 26.11.1-SNAPSHOT (build b91b5fd0), started with -Darcadedb.server.defaultDatabases=test[root]. Each statement below is one POST /api/v1/command/test request with the given language.

sqlscript: CREATE TIMESERIES TYPE Ev TIMESTAMP ts PRECISION MILLISECOND TAGS (k STRING) FIELDS (v DOUBLE);
           INSERT INTO Ev SET ts = 1792396800000, k = 'a', v = 1.0;
           INSERT INTO Ev SET ts = 1792396860000, k = 'a', v = 2.0;
sql:    SELECT count(*) AS n FROM Ev
  -> [{"n":2}]
cypher: MATCH (e:Ev) RETURN count(e) AS n
  -> [{"n":0}]
cypher: MATCH (e:Ev) RETURN e LIMIT 1
  -> []

Expected

One of these:

• Cypher scans a time-series type the way SQL FROM does (an aggregation over it shows AGGREGATE FROM TIMESERIES in EXPLAIN), so MATCH (e:Ev) returns the samples as nodes with their timestamp, tags and fields.
• MATCH on a time-series label fails with an error saying that Cypher does not query time-series types, and the docs table is corrected (I can do the docs side).

Silently returning zero rows is the worst of the options, because it looks like a correct answer.