ORDER BY

Generic Description

Sort rows by one or more expressions.

Simple example:

MATCH (p:Person) RETURN p.name ORDER BY p.name

Consumer-Level Explanation

Use ORDER BY when the query must sort rows by one or more expressions and the planner needs to see that operation as part of the Cypher row pipeline. Keep the clause explicit because it controls row grain, variable scope, and what later clauses are allowed to reference.

More Detailed Explanation

ORDER BY is not just for presentation. In real workloads it stabilizes pagination, ranking, top-k selection, and deterministic API output. Combined with vector or temporal scoring, it becomes the final control point for relevance or recency.

What this clause is really for:

it defines one concrete stage in the Cypher row pipeline, so variables available before and after ORDER BY must be clear
it should make graph structure, temporal filters, document payload shaping, or procedure output explicit instead of relying on client-side interpretation
planner tooling depends on this clause boundary to know row grain, variable scope, and whether later expressions are reads, writes, schema operations, or projections

Advanced Example

This example keeps ORDER BY inside a complete query pipeline so the clause boundary, visible variables, and returned row shape are clear to planner tooling.

MATCH (u:User)-[e:VIEWED]->(d:Document)
TIME e.ts BETWEEN datetime('2025-01-01T00:00:00Z') AND datetime('2025-02-01T00:00:00Z')
WITH u, d, date_trunc('day', e.ts) AS day_bucket,
     unpivot(properties(d.metadata)) AS metadata_rows,
     cosine_similarity(vector(properties(d).embedding), vector([0.22, 0.18, 0.44])) AS score
RETURN u.user_id, d.title, day_bucket, metadata_rows, score
ORDER BY day_bucket DESC, score DESC
SKIP 20
LIMIT 10

Real Use Cases

relevance ranking after vector or semantic scoring
stable API pagination
top-N operational dashboards

Real Limitations And Tradeoffs

sorting large intermediate result sets is expensive
pagination without deterministic ordering is fragile
sorting after unnecessary row explosion wastes work