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<h1 class="title">PostgreSQL 18.3 Documentation</h1>
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<h3 class="corpauthor">The PostgreSQL Global Development Group</h3>
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<p class="copyright">Copyright © 1996–2026 The PostgreSQL Global Development Group</p>
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<p><strong>Table of Contents</strong></p>
<dl class="toc">
<dt><span class="preface"><a href="/docs/current/preface.html">Preface</a></span></dt>
<dd>
<dl>
<dt><span class="sect1"><a href="/docs/current/intro-whatis.html">1. What Is <span class="productname">PostgreSQL</span>?</a></span></dt>
<dt><span class="sect1"><a href="/docs/current/history.html">2. A Brief History of <span class="productname">PostgreSQL</span></a></span></dt>
<dt><span class="sect1"><a href="/docs/current/notation.html">3. Conventions</a></span></dt>
<dt><span class="sect1"><a href="/docs/current/resources.html">4. Further Information</a></span></dt>
<dt><span class="sect1"><a href="/docs/current/bug-reporting.html">5. Bug Reporting Guidelines</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/tutorial.html">I. Tutorial</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/tutorial-start.html">1. Getting Started</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/tutorial-sql.html">2. The <acronym class="acronym">SQL</acronym> Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/tutorial-advanced.html">3. Advanced Features</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/sql.html">II. The SQL Language</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/sql-syntax.html">4. SQL Syntax</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/ddl.html">5. Data Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/dml.html">6. Data Manipulation</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/queries.html">7. Queries</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/datatype.html">8. Data Types</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/functions.html">9. Functions and Operators</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/typeconv.html">10. Type Conversion</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/indexes.html">11. Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/textsearch.html">12. Full Text Search</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/mvcc.html">13. Concurrency Control</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/performance-tips.html">14. Performance Tips</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/parallel-query.html">15. Parallel Query</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/admin.html">III. Server Administration</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/install-binaries.html">16. Installation from Binaries</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/installation.html">17. Installation from Source Code</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/runtime.html">18. Server Setup and Operation</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/runtime-config.html">19. Server Configuration</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/client-authentication.html">20. Client Authentication</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/user-manag.html">21. Database Roles</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/managing-databases.html">22. Managing Databases</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/charset.html">23. Localization</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/maintenance.html">24. Routine Database Maintenance Tasks</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/backup.html">25. Backup and Restore</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/high-availability.html">26. High Availability, Load Balancing, and Replication</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/monitoring.html">27. Monitoring Database Activity</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/wal.html">28. Reliability and the Write-Ahead Log</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/logical-replication.html">29. Logical Replication</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/jit.html">30. Just-in-Time Compilation (<acronym class="acronym">JIT</acronym>)</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/regress.html">31. Regression Tests</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/client-interfaces.html">IV. Client Interfaces</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/libpq.html">32. <span class="application">libpq</span> — C Library</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/largeobjects.html">33. Large Objects</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/ecpg.html">34. <span class="application">ECPG</span> — Embedded <acronym class="acronym">SQL</acronym> in C</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/information-schema.html">35. The Information Schema</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/server-programming.html">V. Server Programming</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/extend.html">36. Extending <acronym class="acronym">SQL</acronym></a></span></dt>
<dt><span class="chapter"><a href="/docs/current/triggers.html">37. Triggers</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/event-triggers.html">38. Event Triggers</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/rules.html">39. The Rule System</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/xplang.html">40. Procedural Languages</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/plpgsql.html">41. <span class="application">PL/pgSQL</span> — <acronym class="acronym">SQL</acronym> Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/pltcl.html">42. PL/Tcl — Tcl Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/plperl.html">43. PL/Perl — Perl Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/plpython.html">44. PL/Python — Python Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/spi.html">45. Server Programming Interface</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/bgworker.html">46. Background Worker Processes</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/logicaldecoding.html">47. Logical Decoding</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/replication-origins.html">48. Replication Progress Tracking</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/archive-modules.html">49. Archive Modules</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/oauth-validators.html">50. OAuth Validator Modules</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/reference.html">VI. Reference</a></span></dt>
<dd>
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<dt><span class="reference"><a href="/docs/current/sql-commands.html">I. SQL Commands</a></span></dt>
<dt><span class="reference"><a href="/docs/current/reference-client.html">II. PostgreSQL Client Applications</a></span></dt>
<dt><span class="reference"><a href="/docs/current/reference-server.html">III. PostgreSQL Server Applications</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/internals.html">VII. Internals</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/current/overview.html">51. Overview of PostgreSQL Internals</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/catalogs.html">52. System Catalogs</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/views.html">53. System Views</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/protocol.html">54. Frontend/Backend Protocol</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/source.html">55. PostgreSQL Coding Conventions</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/nls.html">56. Native Language Support</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/plhandler.html">57. Writing a Procedural Language Handler</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/fdwhandler.html">58. Writing a Foreign Data Wrapper</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/tablesample-method.html">59. Writing a Table Sampling Method</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/custom-scan.html">60. Writing a Custom Scan Provider</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/geqo.html">61. Genetic Query Optimizer</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/tableam.html">62. Table Access Method Interface Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/indexam.html">63. Index Access Method Interface Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/wal-for-extensions.html">64. Write Ahead Logging for Extensions</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/indextypes.html">65. Built-in Index Access Methods</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/storage.html">66. Database Physical Storage</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/transactions.html">67. Transaction Processing</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/bki.html">68. System Catalog Declarations and Initial Contents</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/planner-stats-details.html">69. How the Planner Uses Statistics</a></span></dt>
<dt><span class="chapter"><a href="/docs/current/backup-manifest-format.html">70. Backup Manifest Format</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/current/appendixes.html">VIII. Appendixes</a></span></dt>
<dd>
<dl>
<dt><span class="appendix"><a href="/docs/current/errcodes-appendix.html">A. <span class="productname">PostgreSQL</span> Error Codes</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/datetime-appendix.html">B. Date/Time Support</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/sql-keywords-appendix.html">C. <acronym class="acronym">SQL</acronym> Key Words</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/features.html">D. SQL Conformance</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/release.html">E. Release Notes</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/contrib.html">F. Additional Supplied Modules and Extensions</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/contrib-prog.html">G. Additional Supplied Programs</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/external-projects.html">H. External Projects</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/sourcerepo.html">I. The Source Code Repository</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/docguide.html">J. Documentation</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/limits.html">K. <span class="productname">PostgreSQL</span> Limits</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/acronyms.html">L. Acronyms</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/glossary.html">M. Glossary</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/color.html">N. Color Support</a></span></dt>
<dt><span class="appendix"><a href="/docs/current/appendix-obsolete.html">O. Obsolete or Renamed Features</a></span></dt>
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<dt><span class="bibliography"><a href="/docs/current/biblio.html">Bibliography</a></span></dt>
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