---
title: CALL
url: https://nexyron.tech/docs/cypher/clauses/procedural/call
description: Invoke a row producing procedure and optionally project selected outputs with YIELD.
---

# CALL

## Generic Description

Invoke a row-producing procedure and optionally project selected outputs with YIELD.

Simple example:

```cypher
CALL nexyron.pagerank() YIELD node_id, score RETURN node_id, score
```

## Consumer-Level Explanation

Use `CALL` when the query must invoke a row-producing procedure and optionally project selected outputs with YIELD 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

CALL is how Nexyron exposes algorithmic and semantic capabilities without inventing a second query language. It lets procedures behave like row sources that can be joined back to graph entities, filtered, ranked, or fed into later query stages.

What this clause is really for:

-   it defines one concrete stage in the Cypher row pipeline, so variables available before and after `CALL` 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 `CALL` inside a complete query pipeline so the clause boundary, visible variables, and returned row shape are clear to planner tooling.

```cypher
CALL nexyron.pagerank() YIELD node_id, score
RETURN node_id, score
ORDER BY score DESC
LIMIT 10
```

## Real Use Cases

-   running graph algorithms inline with graph filters
-   semantic or MMR search from Cypher
-   projection lifecycle management from query code

## Real Limitations And Tradeoffs

-   procedure signatures vary and should be verified from the registry
-   YIELD column names must match the real procedure output
-   heavy procedure pipelines benefit from clear staging with WITH
