EXPLAIN Command | Geode Database

<h2 id="explain-command" class="position-relative d-flex align-items-center group"> EXPLAIN Command <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="explain-command" aria-haspopup="dialog" aria-label="Share link: EXPLAIN Command"> 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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Use it to understand how Geode will process your queries and identify optimization opportunities. <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> <h4 id="what-explain-does" class="position-relative d-flex align-items-center group"> What EXPLAIN Does <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="what-explain-does" aria-haspopup="dialog" aria-label="Share link: What EXPLAIN Does"> Share link </button> </h4><ul> <li>Parses and plans the query</li> <li>Returns the logical execution plan</li> <li>Does NOT execute the query</li> <li>Does NOT access data</li> <li>Zero-cost operation (safe for production)</li> </ul> <h4 id="when-to-use-explain" class="position-relative d-flex align-items-center group"> When to 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="when-to-use-explain" aria-haspopup="dialog" aria-label="Share link: When to Use EXPLAIN"> Share link </button> </h4><ul> <li>Before running expensive queries</li> <li>When optimizing query performance</li> <li>To verify index usage</li> <li>When comparing query alternatives</li> <li>For understanding query processing</li> </ul> <h3 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> </h3><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN <statement> </code></pre></div>The EXPLAIN keyword prefixes any GQL statement: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (n:Person) RETURN n.name; EXPLAIN CREATE (p:Person {name: 'Alice'}); EXPLAIN MATCH (a)-[:KNOWS]->(b) DELETE a; </code></pre></div> <h3 id="basic-examples" class="position-relative d-flex align-items-center group"> Basic 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="basic-examples" aria-haspopup="dialog" aria-label="Share link: Basic Examples"> Share link </button> </h3> <h4 id="simple-match-query" class="position-relative d-flex align-items-center group"> Simple MATCH Query <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="simple-match-query" aria-haspopup="dialog" aria-label="Share link: Simple MATCH Query"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person) RETURN p.name; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------| | EXPLAIN | | MATCH | | NodeScan | | RETURN | | Project | </code></pre></div>Reading the Plan: <ul> <li><code>NodeScan</code>: Scans nodes with the Person label</li> <li><code>Project</code>: Selects the <code>name</code> property for output</li> </ul> <h4 id="match-with-where" class="position-relative d-flex align-items-center group"> MATCH with 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="match-with-where" aria-haspopup="dialog" aria-label="Share link: MATCH with WHERE"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person) WHERE p.age > 30 RETURN p.name, p.age; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------| | EXPLAIN | | MATCH | | NodeScan | | Filter | | RETURN | | Project | </code></pre></div>New Operator: <ul> <li><code>Filter</code>: Applies the <code>WHERE p.age > 30</code> predicate</li> </ul> <h4 id="relationship-pattern" class="position-relative d-flex align-items-center group"> Relationship Pattern <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-pattern" aria-haspopup="dialog" aria-label="Share link: Relationship Pattern"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (a:Person)-[:KNOWS]->(b:Person) RETURN a.name, b.name; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------------| | EXPLAIN | | MATCH | | NodeScan | | ExpandRelationships | | RETURN | | Project | </code></pre></div>New Operator: <ul> <li><code>ExpandRelationships</code>: Traverses KNOWS relationships</li> </ul> <h3 id="execution-plan-operators" class="position-relative d-flex align-items-center group"> Execution Plan Operators <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="execution-plan-operators" aria-haspopup="dialog" aria-label="Share link: Execution Plan Operators"> Share link </button> </h3> <h4 id="scan-operators" class="position-relative d-flex align-items-center group"> Scan Operators <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="scan-operators" aria-haspopup="dialog" aria-label="Share link: Scan Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>NodeScan</code></td> <td>Scans nodes (optionally by label)</td> <td>MATCH clauses</td> </tr> <tr> <td><code>IndexScan</code></td> <td>Uses index to find nodes</td> <td>Indexed property lookups</td> </tr> <tr> <td><code>UniqueIndexScan</code></td> <td>Uses unique index</td> <td>Unique constraint lookups</td> </tr> </tbody> </table> <h4 id="filter-operators" class="position-relative d-flex align-items-center group"> Filter Operators <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="filter-operators" aria-haspopup="dialog" aria-label="Share link: Filter Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>Filter</code></td> <td>Applies WHERE predicates</td> <td>WHERE clauses</td> </tr> <tr> <td><code>LabelFilter</code></td> <td>Filters by label</td> <td>Multiple labels</td> </tr> </tbody> </table> <h4 id="traversal-operators" class="position-relative d-flex align-items-center group"> Traversal Operators <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="traversal-operators" aria-haspopup="dialog" aria-label="Share link: Traversal Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>ExpandRelationships</code></td> <td>Follows relationships</td> <td>Relationship patterns</td> </tr> <tr> <td><code>VarLengthExpand</code></td> <td>Variable-length traversal</td> <td><code>*1..3</code> patterns</td> </tr> <tr> <td><code>ShortestPath</code></td> <td>Computes shortest path</td> <td>shortestPath()</td> </tr> </tbody> </table> <h4 id="aggregation-operators" class="position-relative d-flex align-items-center group"> Aggregation Operators <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="aggregation-operators" aria-haspopup="dialog" aria-label="Share link: Aggregation Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>Aggregate</code></td> <td>Groups and computes aggregates</td> <td>COUNT, SUM, etc.</td> </tr> <tr> <td><code>Distinct</code></td> <td>Removes duplicates</td> <td>DISTINCT keyword</td> </tr> </tbody> </table> <h4 id="modification-operators" class="position-relative d-flex align-items-center group"> Modification Operators <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="modification-operators" aria-haspopup="dialog" aria-label="Share link: Modification Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>CreateNodes</code></td> <td>Creates new nodes</td> <td>CREATE</td> </tr> <tr> <td><code>CreateRelationships</code></td> <td>Creates relationships</td> <td>CREATE</td> </tr> <tr> <td><code>DeleteNodes</code></td> <td>Deletes nodes</td> <td>DELETE</td> </tr> <tr> <td><code>SetProperties</code></td> <td>Updates properties</td> <td>SET</td> </tr> </tbody> </table> <h4 id="other-operators" class="position-relative d-flex align-items-center group"> Other Operators <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="other-operators" aria-haspopup="dialog" aria-label="Share link: Other Operators"> Share link </button> </h4><table> <thead> <tr> <th>Operator</th> <th>Description</th> <th>When Used</th> </tr> </thead> <tbody> <tr> <td><code>Project</code></td> <td>Selects/transforms columns</td> <td>RETURN</td> </tr> <tr> <td><code>Sort</code></td> <td>Orders results</td> <td>ORDER BY</td> </tr> <tr> <td><code>Limit</code></td> <td>Restricts row count</td> <td>LIMIT</td> </tr> <tr> <td><code>Skip</code></td> <td>Skips rows</td> <td>OFFSET/SKIP</td> </tr> </tbody> </table> <h3 id="complex-query-examples" class="position-relative d-flex align-items-center group"> Complex Query 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="complex-query-examples" aria-haspopup="dialog" aria-label="Share link: Complex Query Examples"> Share link </button> </h3> <h4 id="aggregation-query" class="position-relative d-flex align-items-center group"> Aggregation Query <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="aggregation-query" aria-haspopup="dialog" aria-label="Share link: Aggregation Query"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person)-[:WORKS_FOR]->(c:Company) WHERE p.age > 25 RETURN c.name, count(p) AS employee_count ORDER BY employee_count DESC LIMIT 10; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------------| | EXPLAIN | | MATCH | | NodeScan | | ExpandRelationships | | Filter | | RETURN | | Aggregate | | Project | | Sort | | Limit | </code></pre></div> <h4 id="variable-length-path" class="position-relative d-flex align-items-center group"> Variable-Length 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="variable-length-path" aria-haspopup="dialog" aria-label="Share link: Variable-Length Path"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH path = (a:Person {name: 'Alice'})-[:KNOWS*1..3]->(b:Person) RETURN path; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------------| | EXPLAIN | | MATCH | | NodeScan | | Filter | | VarLengthExpand | | RETURN | | Project | </code></pre></div> <h4 id="create-statement" class="position-relative d-flex align-items-center group"> CREATE Statement <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="create-statement" aria-haspopup="dialog" aria-label="Share link: CREATE Statement"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN CREATE (p:Person {name: 'Bob', age: 30}) -[:WORKS_FOR]-> (c:Company {name: 'Acme'}); </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------------| | EXPLAIN | | CREATE | | CreateNodes | | CreateRelationships | </code></pre></div> <h4 id="delete-statement" class="position-relative d-flex align-items-center group"> DELETE Statement <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="delete-statement" aria-haspopup="dialog" aria-label="Share link: DELETE Statement"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person) WHERE p.status = 'inactive' DETACH DELETE p; </code></pre></div>Output: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------------| | EXPLAIN | | DELETE | | NodeScan | | Filter | | DeleteNodes | </code></pre></div> <h3 id="interpreting-plans" class="position-relative d-flex align-items-center group"> Interpreting Plans <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="interpreting-plans" aria-haspopup="dialog" aria-label="Share link: Interpreting Plans"> Share link </button> </h3> <h4 id="reading-plan-order" class="position-relative d-flex align-items-center group"> Reading Plan Order <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="reading-plan-order" aria-haspopup="dialog" aria-label="Share link: Reading Plan Order"> Share link </button> </h4>Plans execute from innermost to outermost: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| EXPLAIN | <- Final output | MATCH | | NodeScan | <- Start here | Filter | <- Then filter | RETURN | | Project | <- Finally project </code></pre></div>Execution flow: NodeScan -> Filter -> Project <h4 id="identifying-issues" class="position-relative d-flex align-items-center group"> Identifying Issues <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="identifying-issues" aria-haspopup="dialog" aria-label="Share link: Identifying Issues"> Share link </button> </h4>Issue: Full Node Scan <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| NodeScan | <- No label = scans ALL nodes </code></pre></div>Solution: Add label to pattern: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">MATCH (p:Person) -- Scans only Person nodes </code></pre></div>Issue: Late Filtering <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| NodeScan | | ExpandRelationships | <- Expands before filter | Filter | <- Filter applied late </code></pre></div>Solution: Move filter to pattern or earlier WHERE: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">MATCH (p:Person {status: 'active'})-[:KNOWS]->(f) -- OR use WITH to filter before expanding MATCH (p:Person) WHERE p.status = 'active' WITH p MATCH (p)-[:KNOWS]->(f) </code></pre></div> <h4 id="plan-comparison" class="position-relative d-flex align-items-center group"> Plan Comparison <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="plan-comparison" aria-haspopup="dialog" aria-label="Share link: Plan Comparison"> Share link </button> </h4>Compare different query formulations: Query A: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person), (c:Company) WHERE p.company_id = c.id RETURN p.name, c.name; </code></pre></div>Query B: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person)-[:WORKS_FOR]->(c:Company) RETURN p.name, c.name; </code></pre></div>Query B is likely more efficient (uses relationship vs. property join). <h3 id="explain-for-optimization" class="position-relative d-flex align-items-center group"> EXPLAIN for Optimization <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="explain-for-optimization" aria-haspopup="dialog" aria-label="Share link: EXPLAIN for Optimization"> Share link </button> </h3> <h4 id="workflow" class="position-relative d-flex align-items-center group"> Workflow <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="workflow" aria-haspopup="dialog" aria-label="Share link: Workflow"> Share link </button> </h4><ol> <li>Write query</li> <li>Run EXPLAIN</li> <li>Analyze plan</li> <li>Identify issues</li> <li>Refactor query</li> <li>Repeat</li> </ol> <h4 id="optimization-checklist" class="position-relative d-flex align-items-center group"> Optimization Checklist <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="optimization-checklist" aria-haspopup="dialog" aria-label="Share link: Optimization Checklist"> Share link </button> </h4>Check EXPLAIN output for: <ul> <li><input disabled="" type="checkbox"> <code>NodeScan</code> without label filter?</li> <li><input disabled="" type="checkbox"> <code>Filter</code> after expensive operations?</li> <li><input disabled="" type="checkbox"> Missing index usage?</li> <li><input disabled="" type="checkbox"> Unnecessary <code>Sort</code> operations?</li> <li><input disabled="" type="checkbox"> <code>VarLengthExpand</code> without bounds?</li> </ul> <h4 id="example-optimization" class="position-relative d-flex align-items-center group"> Example Optimization <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="example-optimization" aria-haspopup="dialog" aria-label="Share link: Example Optimization"> Share link </button> </h4>Before: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (n) WHERE n:Person AND n.email = 'alice@example.com' RETURN n; </code></pre></div><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------| | EXPLAIN | | MATCH | | NodeScan | <- Scans all nodes! | LabelFilter | | Filter | </code></pre></div>After: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Create index CREATE INDEX person_email ON Person(email); EXPLAIN MATCH (n:Person {email: 'alice@example.com'}) RETURN n; </code></pre></div><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-fallback" data-lang="fallback">| plan | |-------------------| | EXPLAIN | | MATCH | | IndexScan | <- Uses index! </code></pre></div> <h3 id="limitations" class="position-relative d-flex align-items-center group"> Limitations <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="limitations" aria-haspopup="dialog" aria-label="Share link: Limitations"> Share link </button> </h3> <h4 id="current-limitations" class="position-relative d-flex align-items-center group"> Current Limitations <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="current-limitations" aria-haspopup="dialog" aria-label="Share link: Current Limitations"> Share link </button> </h4><ol> <li>No Cost Estimates: Plans don’t show estimated costs</li> <li>No Row Estimates: No estimated row counts per operator</li> <li>No Index Details: Doesn’t show which specific index is used</li> <li>No Memory Estimates: Memory usage not shown</li> </ol> <h4 id="future-enhancements" class="position-relative d-flex align-items-center group"> Future Enhancements <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="future-enhancements" aria-haspopup="dialog" aria-label="Share link: Future Enhancements"> Share link </button> </h4>Planned improvements include: <ul> <li>Cost-based plan display</li> <li>Row count estimates</li> <li>Index usage details</li> <li>Memory allocation estimates</li> <li>Visual plan representation</li> </ul> <h3 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> </h3> <h4 id="when-to-use-explain-1" class="position-relative d-flex align-items-center group"> When to 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="when-to-use-explain-1" aria-haspopup="dialog" aria-label="Share link: When to Use EXPLAIN"> Share link </button> </h4>DO use EXPLAIN: <ul> <li>Before deploying new queries</li> <li>When queries are slow</li> <li>To verify index usage</li> <li>When comparing query alternatives</li> </ul> DON’T rely only on EXPLAIN: <ul> <li>Use PROFILE for actual performance data</li> <li>Real execution may differ from plan</li> </ul> <h4 id="production-safety" class="position-relative d-flex align-items-center group"> Production Safety <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="production-safety" aria-haspopup="dialog" aria-label="Share link: Production Safety"> Share link </button> </h4>EXPLAIN is safe for production: <ul> <li>No data access</li> <li>No locks acquired</li> <li>No side effects</li> <li>Fast execution</li> </ul> <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">-- Safe to run in production EXPLAIN MATCH (n:CriticalData) RETURN count(n); </code></pre></div> <h3 id="related-commands" class="position-relative d-flex align-items-center group"> Related Commands <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-commands" aria-haspopup="dialog" aria-label="Share link: Related Commands"> Share link </button> </h3> <h4 id="profile" class="position-relative d-flex align-items-center group"> PROFILE <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="profile" aria-haspopup="dialog" aria-label="Share link: PROFILE"> Share link </button> </h4>Execute query and measure actual performance: <div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">PROFILE MATCH (p:Person) WHERE p.age > 30 RETURN p.name; </code></pre></div>See <a href="/docs/gql-reference/profile/" >PROFILE Command</a> for details. <h4 id="comparison" class="position-relative d-flex align-items-center group"> Comparison <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="comparison" aria-haspopup="dialog" aria-label="Share link: Comparison"> Share link </button> </h4><table> <thead> <tr> <th>Aspect</th> <th>EXPLAIN</th> <th>PROFILE</th> </tr> </thead> <tbody> <tr> <td>Executes query</td> <td>No</td> <td>Yes</td> </tr> <tr> <td>Shows plan</td> <td>Yes</td> <td>Yes (with metrics)</td> </tr> <tr> <td>Safe for production</td> <td>Yes</td> <td>Use with caution</td> </tr> <tr> <td>Performance impact</td> <td>None</td> <td>Query execution time</td> </tr> <tr> <td>Best for</td> <td>Planning</td> <td>Measuring</td> </tr> </tbody> </table> <h3 id="examples-by-query-type" class="position-relative d-flex align-items-center group"> Examples by Query Type <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-by-query-type" aria-haspopup="dialog" aria-label="Share link: Examples by Query Type"> Share link </button> </h3> <h4 id="selectmatch-queries" class="position-relative d-flex align-items-center group"> SELECT/MATCH Queries <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="selectmatch-queries" aria-haspopup="dialog" aria-label="Share link: SELECT/MATCH Queries"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person)-[:FRIENDS]->(f:Person) WHERE p.name = 'Alice' RETURN f.name; </code></pre></div> <h4 id="aggregation-queries" class="position-relative d-flex align-items-center group"> Aggregation Queries <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="aggregation-queries" aria-haspopup="dialog" aria-label="Share link: Aggregation Queries"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (o:Order) RETURN o.category, sum(o.total) AS revenue ORDER BY revenue DESC; </code></pre></div> <h4 id="path-queries" class="position-relative d-flex align-items-center group"> Path Queries <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-queries" aria-haspopup="dialog" aria-label="Share link: Path Queries"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH path = shortestPath( (a:Person {name: 'Alice'})-[*]-(b:Person {name: 'Bob'}) ) RETURN path; </code></pre></div> <h4 id="mutation-queries" class="position-relative d-flex align-items-center group"> Mutation Queries <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="mutation-queries" aria-haspopup="dialog" aria-label="Share link: Mutation Queries"> Share link </button> </h4><div class="highlight"><pre tabindex="0" class="chroma"><code class="language-gql" data-lang="gql">EXPLAIN MATCH (p:Person {status: 'inactive'}) SET p.archived = true; </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/gql-reference/profile/" >PROFILE Command</a> - Measure actual performance</li> <li><a href="/docs/query/performance-tuning/" >Query Performance Tuning</a> - Optimization guide</li> <li><a href="/docs/query/indexing-and-optimization/" >Indexing Guide</a> - Index strategies</li> <li><a href="/docs/gql/guide/" >GQL Guide</a> - Complete GQL reference</li> </ul> <hr> Last Updated: January 28, 2026 Geode Version: v0.2.18+ GQL Compliance: ISO/IEC 39075:2024