Pattern Matching in GQL | Geode Database

<h2 id="pattern-matching-in-gql" class="position-relative d-flex align-items-center group"> Pattern Matching in GQL <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-matching-in-gql" aria-haspopup="dialog" aria-label="Share link: Pattern Matching in GQL"> Share link </button> </h2><div id="headingShareModal" class="heading-share-modal" role="dialog" aria-modal="true" aria-labelledby="headingShareTitle" hidden> <div class="hsm-dialog" role="document"> <div class="hsm-header"> <h2 id="headingShareTitle" class="h6 mb-0 fw-bold">Share this section</h2> <button type="button" class="hsm-close" aria-label="Close"> </button> </div> <div class="hsm-body"> <label for="headingShareInput" class="form-label small text-muted mb-1 text-uppercase fw-bold" style="font-size: 0.7rem; letter-spacing: 0.5px;">Permalink</label> <div class="input-group mb-4 hsm-url-group"> <input id="headingShareInput" type="text" class="form-control font-monospace" readonly aria-readonly="true" style="font-size: 0.85rem;" /> <button class="btn btn-primary hsm-copy" type="button" aria-label="Copy" title="Copy"> </button> </div> <div class="small fw-bold mb-2 text-muted text-uppercase" style="font-size: 0.7rem; 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This reference covers all pattern types and their usage in Geode. <h3 id="overview" class="position-relative d-flex align-items-center group"> Overview <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="overview" aria-haspopup="dialog" aria-label="Share link: Overview"> Share link </button> </h3>Patterns describe graph structures to match. They consist of: <ul> <li>Node patterns: Match nodes</li> <li>Relationship patterns: Match relationships between nodes</li> <li>Path patterns: Match sequences of nodes and relationships</li> </ul> <h3 id="node-patterns" class="position-relative d-flex align-items-center group"> Node Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="node-patterns" aria-haspopup="dialog" aria-label="Share link: Node Patterns"> Share link </button> </h3> <h4 id="basic-syntax" class="position-relative d-flex align-items-center group"> Basic Syntax <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="basic-syntax" aria-haspopup="dialog" aria-label="Share link: Basic Syntax"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">(variable:Label {property: value}) </code></pre></div><table> <thead> <tr> <th>Component</th> <th>Description</th> <th>Required</th> </tr> </thead> <tbody> <tr> <td><code>variable</code></td> <td>Variable name for referencing</td> <td>No</td> </tr> <tr> <td><code>Label</code></td> <td>Node label(s)</td> <td>No</td> </tr> <tr> <td><code>{...}</code></td> <td>Property constraints</td> <td>No</td> </tr> </tbody> </table> <h4 id="examples" class="position-relative d-flex align-items-center group"> Examples <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="examples" aria-haspopup="dialog" aria-label="Share link: Examples"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Any node (n) -- Node with label (p:Person) -- Anonymous node (no variable) (:Person) -- Node with property constraint (p:Person {name: 'Alice'}) -- Node with multiple properties (p:Person {name: 'Alice', age: 30}) -- Node with multiple labels (e:Person:Employee) -- Just properties, no label (n {status: 'active'}) </code></pre></div> <h4 id="multiple-labels" class="position-relative d-flex align-items-center group"> Multiple Labels <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="multiple-labels" aria-haspopup="dialog" aria-label="Share link: Multiple Labels"> Share link </button> </h4>Nodes can have multiple labels. Match nodes with specific label combinations: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Match nodes with both Person AND Employee labels MATCH (e:Person:Employee) RETURN e.name; -- Match nodes with Person label (may have other labels too) MATCH (p:Person) RETURN p.name, labels(p); </code></pre></div> <h4 id="property-constraints" class="position-relative d-flex align-items-center group"> Property Constraints <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="property-constraints" aria-haspopup="dialog" aria-label="Share link: Property Constraints"> Share link </button> </h4>Property constraints filter nodes during matching: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Exact match (p:Person {name: 'Alice'}) -- Multiple property constraints (AND) (p:Person {name: 'Alice', city: 'Seattle'}) -- Dynamic values using parameters (p:Person {id: $user_id}) </code></pre></div>Note: For complex filtering (comparisons, OR, etc.), use WHERE clause: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">MATCH (p:Person) WHERE p.age > 30 AND p.city IN ['Seattle', 'Portland'] RETURN p.name; </code></pre></div> <h3 id="relationship-patterns" class="position-relative d-flex align-items-center group"> Relationship Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="relationship-patterns" aria-haspopup="dialog" aria-label="Share link: Relationship Patterns"> Share link </button> </h3> <h4 id="basic-syntax-1" class="position-relative d-flex align-items-center group"> Basic Syntax <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="basic-syntax-1" aria-haspopup="dialog" aria-label="Share link: Basic Syntax"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-[variable:TYPE {property: value}]-> </code></pre></div><table> <thead> <tr> <th>Component</th> <th>Description</th> <th>Required</th> </tr> </thead> <tbody> <tr> <td><code>-</code> or <code><-</code></td> <td>Left connection</td> <td>Yes</td> </tr> <tr> <td><code>[...]</code></td> <td>Relationship details</td> <td>No</td> </tr> <tr> <td><code>variable</code></td> <td>Variable name</td> <td>No</td> </tr> <tr> <td><code>TYPE</code></td> <td>Relationship type</td> <td>No</td> </tr> <tr> <td><code>{...}</code></td> <td>Property constraints</td> <td>No</td> </tr> <tr> <td><code>-></code> or <code>-</code></td> <td>Right connection</td> <td>Yes</td> </tr> </tbody> </table> <h4 id="direction" class="position-relative d-flex align-items-center group"> Direction <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="direction" aria-haspopup="dialog" aria-label="Share link: Direction"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Outgoing relationship (left to right) (a)-[:KNOWS]->(b) -- Incoming relationship (right to left) (a)<-[:KNOWS]-(b) -- Undirected (either direction) (a)-[:KNOWS]-(b) </code></pre></div> <h4 id="examples-1" class="position-relative d-flex align-items-center group"> Examples <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="examples-1" aria-haspopup="dialog" aria-label="Share link: Examples"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Any relationship (a)-[r]->(b) -- Typed relationship (a)-[:KNOWS]->(b) -- Named relationship with type (a)-[k:KNOWS]->(b) -- Relationship with properties (a)-[k:KNOWS {since: 2020}]->(b) -- Anonymous relationship (a)-[:KNOWS]->() -- Multiple relationship types (OR) (a)-[:KNOWS|:FOLLOWS]->(b) -- Any relationship type (a)-[r]->(b) </code></pre></div> <h4 id="multiple-relationship-types" class="position-relative d-flex align-items-center group"> Multiple Relationship Types <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="multiple-relationship-types" aria-haspopup="dialog" aria-label="Share link: Multiple Relationship Types"> Share link </button> </h4>Match any of several relationship types: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Either KNOWS or FOLLOWS MATCH (a:Person)-[:KNOWS|:FOLLOWS]->(b:Person) RETURN a.name, b.name; -- Store type in variable MATCH (a:Person)-[r:KNOWS|:FOLLOWS]->(b:Person) RETURN a.name, type(r), b.name; </code></pre></div> <h4 id="relationship-properties" class="position-relative d-flex align-items-center group"> Relationship Properties <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="relationship-properties" aria-haspopup="dialog" aria-label="Share link: Relationship Properties"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Match specific property value MATCH (a)-[k:KNOWS {since: 2020}]->(b) RETURN a.name, b.name; -- Access relationship properties MATCH (a)-[k:KNOWS]->(b) RETURN a.name, b.name, k.since, k.strength; -- Filter relationship properties in WHERE MATCH (a)-[k:KNOWS]->(b) WHERE k.since > 2020 RETURN a.name, b.name; </code></pre></div> <h3 id="path-patterns" class="position-relative d-flex align-items-center group"> Path Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="path-patterns" aria-haspopup="dialog" aria-label="Share link: Path Patterns"> Share link </button> </h3> <h4 id="complete-patterns" class="position-relative d-flex align-items-center group"> Complete Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="complete-patterns" aria-haspopup="dialog" aria-label="Share link: Complete Patterns"> Share link </button> </h4>A path pattern connects multiple node and relationship patterns: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Two-hop path (a)-[:KNOWS]->(b)-[:WORKS_FOR]->(c) -- Named path path = (a)-[:KNOWS]->(b)-[:WORKS_FOR]->(c) </code></pre></div> <h4 id="path-examples" class="position-relative d-flex align-items-center group"> Path Examples <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="path-examples" aria-haspopup="dialog" aria-label="Share link: Path Examples"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Find mutual friends MATCH (alice:Person {name: 'Alice'})-[:KNOWS]->(friend)-[:KNOWS]->(mutual) WHERE mutual <> alice RETURN mutual.name; -- Three-hop pattern MATCH (a:Person)-[:WORKS_FOR]->(c:Company)-[:LOCATED_IN]->(city:City) RETURN a.name, c.name, city.name; -- Diamond pattern MATCH (a)-[:KNOWS]->(b), (a)-[:KNOWS]->(c), (b)-[:KNOWS]->(d), (c)-[:KNOWS]->(d) RETURN a.name, b.name, c.name, d.name; </code></pre></div> <h4 id="named-paths" class="position-relative d-flex align-items-center group"> Named Paths <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="named-paths" aria-haspopup="dialog" aria-label="Share link: Named Paths"> Share link </button> </h4>Capture entire path for analysis: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Capture path MATCH p = (a:Person {name: 'Alice'})-[:KNOWS*]->(b:Person {name: 'Bob'}) RETURN p; -- Path functions MATCH p = (a)-[:KNOWS*1..3]->(b) RETURN nodes(p), -- List of nodes in path relationships(p), -- List of relationships length(p); -- Number of relationships </code></pre></div> <h3 id="variable-length-paths" class="position-relative d-flex align-items-center group"> Variable-Length Paths <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="variable-length-paths" aria-haspopup="dialog" aria-label="Share link: Variable-Length Paths"> Share link </button> </h3> <h4 id="syntax" class="position-relative d-flex align-items-center group"> Syntax <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="syntax" aria-haspopup="dialog" aria-label="Share link: Syntax"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-[:TYPE*min..max]-> </code></pre></div><table> <thead> <tr> <th>Pattern</th> <th>Meaning</th> </tr> </thead> <tbody> <tr> <td><code>*</code></td> <td>Zero or more (any length)</td> </tr> <tr> <td><code>*n</code></td> <td>Exactly n hops</td> </tr> <tr> <td><code>*..n</code></td> <td>Up to n hops (0 to n)</td> </tr> <tr> <td><code>*n..</code></td> <td>n or more hops</td> </tr> <tr> <td><code>*n..m</code></td> <td>Between n and m hops</td> </tr> </tbody> </table> <h4 id="examples-2" class="position-relative d-flex align-items-center group"> Examples <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="examples-2" aria-haspopup="dialog" aria-label="Share link: Examples"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Exactly 2 hops MATCH (a)-[:KNOWS*2]->(b) RETURN a.name, b.name; -- 1 to 3 hops MATCH (a)-[:KNOWS*1..3]->(b) RETURN DISTINCT b.name; -- Up to 5 hops MATCH (a)-[:KNOWS*..5]->(b) RETURN b.name; -- 2 or more hops MATCH (a)-[:KNOWS*2..]->(b) RETURN b.name; -- Any length (use with caution!) MATCH (a)-[:KNOWS*]->(b) RETURN b.name; </code></pre></div> <h4 id="path-variables-with-length" class="position-relative d-flex align-items-center group"> Path Variables with Length <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="path-variables-with-length" aria-haspopup="dialog" aria-label="Share link: Path Variables with Length"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Capture path with variable length MATCH path = (a:Person {name: 'Alice'})-[:KNOWS*1..4]->(b:Person) RETURN [n IN nodes(path) | n.name] AS names, length(path) AS distance; -- Filter by path length MATCH path = (a)-[:KNOWS*]->(b) WHERE length(path) <= 3 RETURN path; </code></pre></div> <h4 id="relationship-variable-in-path" class="position-relative d-flex align-items-center group"> Relationship Variable in Path <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="relationship-variable-in-path" aria-haspopup="dialog" aria-label="Share link: Relationship Variable in Path"> Share link </button> </h4>Access all relationships in variable-length path: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Check all relationship properties MATCH path = (a)-[rels:KNOWS*1..3]->(b) WHERE ALL(r IN rels WHERE r.strength > 0.5) RETURN a.name, b.name; -- Aggregate over relationships MATCH (a)-[rels:TRANSACTION*1..5]->(b) RETURN a.id, b.id, reduce(total = 0, r IN rels | total + r.amount) AS path_total; </code></pre></div> <h3 id="shortest-path" class="position-relative d-flex align-items-center group"> Shortest Path <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="shortest-path" aria-haspopup="dialog" aria-label="Share link: Shortest Path"> Share link </button> </h3> <h4 id="shortestpath" class="position-relative d-flex align-items-center group"> shortestPath <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="shortestpath" aria-haspopup="dialog" aria-label="Share link: shortestPath"> Share link </button> </h4>Find single shortest path: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">MATCH path = shortestPath( (a:Person {name: 'Alice'})-[*]-(b:Person {name: 'Bob'}) ) RETURN path, length(path) AS distance; </code></pre></div> <h4 id="allshortestpaths" class="position-relative d-flex align-items-center group"> allShortestPaths <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="allshortestpaths" aria-haspopup="dialog" aria-label="Share link: allShortestPaths"> Share link </button> </h4>Find all shortest paths (may be multiple with same length): <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">MATCH paths = allShortestPaths( (a:Person {name: 'Alice'})-[*]-(b:Person {name: 'Bob'}) ) RETURN paths; </code></pre></div> <h4 id="constraints-on-shortest-paths" class="position-relative d-flex align-items-center group"> Constraints on Shortest Paths <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="constraints-on-shortest-paths" aria-haspopup="dialog" aria-label="Share link: Constraints on Shortest Paths"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Limit path length MATCH path = shortestPath( (a:Person)-[:KNOWS*..10]-(b:Person) ) RETURN path; -- Specific relationship types MATCH path = shortestPath( (a:City)-[:ROAD|:HIGHWAY*]-(b:City) ) RETURN [n IN nodes(path) | n.name] AS route; -- With WHERE filter MATCH path = shortestPath( (a:Person)-[*]-(b:Person) ) WHERE ALL(n IN nodes(path) WHERE n.active = true) RETURN path; </code></pre></div> <h3 id="optional-match" class="position-relative d-flex align-items-center group"> OPTIONAL MATCH <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="optional-match" aria-haspopup="dialog" aria-label="Share link: OPTIONAL MATCH"> Share link </button> </h3>Match patterns that may not exist: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Include people with no friends MATCH (p:Person) OPTIONAL MATCH (p)-[:KNOWS]->(friend:Person) RETURN p.name, collect(friend.name) AS friends; -- Multiple optional patterns MATCH (u:User) OPTIONAL MATCH (u)-[:PLACED]->(o:Order) OPTIONAL MATCH (u)-[:REVIEWED]->(r:Review) RETURN u.name, count(o) AS orders, count(r) AS reviews; </code></pre></div> <h4 id="optional-vs-regular-match" class="position-relative d-flex align-items-center group"> OPTIONAL vs Regular MATCH <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="optional-vs-regular-match" aria-haspopup="dialog" aria-label="Share link: OPTIONAL vs Regular MATCH"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Regular MATCH: excludes people with no friends MATCH (p:Person)-[:KNOWS]->(friend) RETURN p.name, count(friend); -- OPTIONAL MATCH: includes people with no friends (count = 0) MATCH (p:Person) OPTIONAL MATCH (p)-[:KNOWS]->(friend) RETURN p.name, count(friend); </code></pre></div> <h3 id="pattern-predicates" class="position-relative d-flex align-items-center group"> Pattern Predicates <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-predicates" aria-haspopup="dialog" aria-label="Share link: Pattern Predicates"> Share link </button> </h3> <h4 id="pattern-in-where" class="position-relative d-flex align-items-center group"> Pattern in WHERE <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-in-where" aria-haspopup="dialog" aria-label="Share link: Pattern in WHERE"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Check pattern exists MATCH (p:Person) WHERE (p)-[:KNOWS]->(:Person {name: 'Alice'}) RETURN p.name; -- Check pattern does not exist MATCH (p:Person) WHERE NOT (p)-[:BLOCKED]->() RETURN p.name; </code></pre></div> <h4 id="exists-subquery" class="position-relative d-flex align-items-center group"> EXISTS Subquery <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="exists-subquery" aria-haspopup="dialog" aria-label="Share link: EXISTS Subquery"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Pattern exists MATCH (p:Person) WHERE EXISTS { MATCH (p)-[:PURCHASED]->(prod:Product) WHERE prod.price > 100 } RETURN p.name; </code></pre></div> <h4 id="pattern-expressions" class="position-relative d-flex align-items-center group"> Pattern Expressions <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-expressions" aria-haspopup="dialog" aria-label="Share link: Pattern Expressions"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Count patterns MATCH (p:Person) RETURN p.name, size((p)-[:KNOWS]->()) AS outgoing_knows, size((p)<-[:KNOWS]-()) AS incoming_knows; </code></pre></div> <h3 id="advanced-patterns" class="position-relative d-flex align-items-center group"> Advanced Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="advanced-patterns" aria-haspopup="dialog" aria-label="Share link: Advanced Patterns"> Share link </button> </h3> <h4 id="disconnected-patterns" class="position-relative d-flex align-items-center group"> Disconnected Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="disconnected-patterns" aria-haspopup="dialog" aria-label="Share link: Disconnected Patterns"> Share link </button> </h4>Match independent patterns (creates cartesian product): <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Two separate patterns MATCH (a:Person {city: 'Seattle'}), (b:Company {industry: 'Tech'}) RETURN a.name, b.name; </code></pre></div> <h4 id="self-relationships" class="position-relative d-flex align-items-center group"> Self-Relationships <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="self-relationships" aria-haspopup="dialog" aria-label="Share link: Self-Relationships"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Node related to itself MATCH (n)-[r:LINKS]->(n) RETURN n.name, r.type; </code></pre></div> <h4 id="mutual-relationships" class="position-relative d-flex align-items-center group"> Mutual Relationships <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="mutual-relationships" aria-haspopup="dialog" aria-label="Share link: Mutual Relationships"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Bidirectional friendship MATCH (a:Person)-[:KNOWS]->(b:Person)-[:KNOWS]->(a) RETURN a.name, b.name; </code></pre></div> <h4 id="negative-patterns" class="position-relative d-flex align-items-center group"> Negative Patterns <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="negative-patterns" aria-haspopup="dialog" aria-label="Share link: Negative Patterns"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Not friends MATCH (a:Person), (b:Person) WHERE a <> b AND NOT (a)-[:KNOWS]-(b) RETURN a.name, b.name; </code></pre></div> <h3 id="pattern-matching-performance" class="position-relative d-flex align-items-center group"> Pattern Matching Performance <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="pattern-matching-performance" aria-haspopup="dialog" aria-label="Share link: Pattern Matching Performance"> Share link </button> </h3> <h4 id="best-practices" class="position-relative d-flex align-items-center group"> Best Practices <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="best-practices" aria-haspopup="dialog" aria-label="Share link: Best Practices"> Share link </button> </h4><ol> <li> Start with selective patterns <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Good: Start with specific node MATCH (a:Person {email: 'alice@example.com'})-[:KNOWS]->(b) -- Avoid: Start with broad scan MATCH (a)-[:KNOWS]->(b:Person {email: 'alice@example.com'}) </code></pre></div></li> <li> Use labels <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Good: Labels enable index usage MATCH (p:Person)-[:KNOWS]->(f:Person) -- Avoid: No labels means full scan MATCH (p)-[:KNOWS]->(f) </code></pre></div></li> <li> Limit variable-length paths <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Good: Bounded length MATCH (a)-[:KNOWS*1..5]->(b) -- Dangerous: Unbounded may be slow MATCH (a)-[:KNOWS*]->(b) </code></pre></div></li> <li> Filter early <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Good: Filter in pattern MATCH (p:Person {status: 'active'})-[:KNOWS]->(f) -- Also good: Filter immediately after MATCH (p:Person)-[:KNOWS]->(f) WHERE p.status = 'active' </code></pre></div></li> </ol> <h4 id="use-explain" class="position-relative d-flex align-items-center group"> Use EXPLAIN <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="use-explain" aria-haspopup="dialog" aria-label="Share link: Use EXPLAIN"> Share link </button> </h4>Analyze pattern matching performance: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (a:Person)-[:KNOWS*1..3]->(b:Person) WHERE a.name = 'Alice' RETURN b.name; </code></pre></div> <h3 id="common-pattern-examples" class="position-relative d-flex align-items-center group"> Common Pattern Examples <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="common-pattern-examples" aria-haspopup="dialog" aria-label="Share link: Common Pattern Examples"> Share link </button> </h3> <h4 id="social-network" class="position-relative d-flex align-items-center group"> Social Network <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="social-network" aria-haspopup="dialog" aria-label="Share link: Social Network"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Friends of friends (not direct friends) MATCH (me:Person {name: 'Alice'})-[:KNOWS]->()-[:KNOWS]->(fof) WHERE NOT (me)-[:KNOWS]->(fof) AND me <> fof RETURN DISTINCT fof.name; -- Influence chain MATCH path = (influencer:Person)-[:FOLLOWS*1..3]->(follower:Person) WHERE influencer.verified = true RETURN influencer.name, follower.name, length(path); </code></pre></div> <h4 id="e-commerce" class="position-relative d-flex align-items-center group"> E-Commerce <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="e-commerce" aria-haspopup="dialog" aria-label="Share link: E-Commerce"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Products frequently bought together MATCH (p1:Product)<-[:CONTAINS]-(o:Order)-[:CONTAINS]->(p2:Product) WHERE p1.id < p2.id -- Avoid duplicates RETURN p1.name, p2.name, count(o) AS co_purchase_count ORDER BY co_purchase_count DESC; -- Customer journey MATCH path = (c:Customer)-[:VIEWED*1..5]->(p:Product)-[:PURCHASED]->(p) RETURN c.id, [n IN nodes(path) | n.name]; </code></pre></div> <h4 id="knowledge-graph" class="position-relative d-flex align-items-center group"> Knowledge Graph <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="knowledge-graph" aria-haspopup="dialog" aria-label="Share link: Knowledge Graph"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Concept hierarchy MATCH path = (specific:Concept)-[:IS_A*1..5]->(general:Concept) WHERE specific.name = 'German Shepherd' RETURN [n IN nodes(path) | n.name] AS taxonomy; -- Entity connections MATCH (e1:Entity)-[r*1..2]-(e2:Entity) WHERE e1.name = 'Albert Einstein' RETURN e2.name, [rel IN r | type(rel)] AS connection_types; </code></pre></div> <h3 id="related-documentation" class="position-relative d-flex align-items-center group"> Related Documentation <button type="button" class="h-share btn btn-link p-0 text-decoration-none link-secondary opacity-50 hover-opacity-100 transition-all ms-1" data-share-target="related-documentation" aria-haspopup="dialog" aria-label="Share link: Related Documentation"> Share link </button> </h3><ul> <li><a href="/docs/quick-reference/" >GQL Quick Reference</a> - Quick syntax lookup</li> <li><a href="/docs/gql-tutorial/" >GQL Tutorial</a> - Learn GQL step by step</li> <li><a href="/docs/gql-reference/aggregations/" >Aggregations</a> - Aggregation functions</li> <li><a href="/docs/gql-reference/explain/" >EXPLAIN and PROFILE</a> - Query analysis</li> <li><a href="/docs/query/performance-tuning/" >Query Performance Tuning</a> - Optimization</li> </ul> <hr> Last Updated: January 28, 2026 Geode Version: v0.2.18+ GQL Compliance: ISO/IEC 39075:2024