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<h1 class="title">PostgreSQL 16.13 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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<div class="toc">
<p><strong>Table of Contents</strong></p>
<dl class="toc">
<dt><span class="preface"><a href="/docs/16/preface.html">Preface</a></span></dt>
<dd>
<dl>
<dt><span class="sect1"><a href="/docs/16/intro-whatis.html">1. What Is <span class="productname">PostgreSQL</span>?</a></span></dt>
<dt><span class="sect1"><a href="/docs/16/history.html">2. A Brief History of <span class="productname">PostgreSQL</span></a></span></dt>
<dt><span class="sect1"><a href="/docs/16/notation.html">3. Conventions</a></span></dt>
<dt><span class="sect1"><a href="/docs/16/resources.html">4. Further Information</a></span></dt>
<dt><span class="sect1"><a href="/docs/16/bug-reporting.html">5. Bug Reporting Guidelines</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/tutorial.html">I. Tutorial</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/tutorial-start.html">1. Getting Started</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/tutorial-sql.html">2. The <acronym class="acronym">SQL</acronym> Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/tutorial-advanced.html">3. Advanced Features</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/sql.html">II. The SQL Language</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/sql-syntax.html">4. SQL Syntax</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/ddl.html">5. Data Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/dml.html">6. Data Manipulation</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/queries.html">7. Queries</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/datatype.html">8. Data Types</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/functions.html">9. Functions and Operators</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/typeconv.html">10. Type Conversion</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/indexes.html">11. Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/textsearch.html">12. Full Text Search</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/mvcc.html">13. Concurrency Control</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/performance-tips.html">14. Performance Tips</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/parallel-query.html">15. Parallel Query</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/admin.html">III. Server Administration</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/install-binaries.html">16. Installation from Binaries</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/installation.html">17. Installation from Source Code</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/install-windows.html">18. Installation from Source Code on <span class="productname">Windows</span></a></span></dt>
<dt><span class="chapter"><a href="/docs/16/runtime.html">19. Server Setup and Operation</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/runtime-config.html">20. Server Configuration</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/client-authentication.html">21. Client Authentication</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/user-manag.html">22. Database Roles</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/managing-databases.html">23. Managing Databases</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/charset.html">24. Localization</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/maintenance.html">25. Routine Database Maintenance Tasks</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/backup.html">26. Backup and Restore</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/high-availability.html">27. High Availability, Load Balancing, and Replication</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/monitoring.html">28. Monitoring Database Activity</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/diskusage.html">29. Monitoring Disk Usage</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/wal.html">30. Reliability and the Write-Ahead Log</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/logical-replication.html">31. Logical Replication</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/jit.html">32. Just-in-Time Compilation (<acronym class="acronym">JIT</acronym>)</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/regress.html">33. Regression Tests</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/client-interfaces.html">IV. Client Interfaces</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/libpq.html">34. <span class="application">libpq</span> — C Library</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/largeobjects.html">35. Large Objects</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/ecpg.html">36. <span class="application">ECPG</span> — Embedded <acronym class="acronym">SQL</acronym> in C</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/information-schema.html">37. The Information Schema</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/server-programming.html">V. Server Programming</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/extend.html">38. Extending <acronym class="acronym">SQL</acronym></a></span></dt>
<dt><span class="chapter"><a href="/docs/16/triggers.html">39. Triggers</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/event-triggers.html">40. Event Triggers</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/rules.html">41. The Rule System</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/xplang.html">42. Procedural Languages</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/plpgsql.html">43. <span class="application">PL/pgSQL</span> — <acronym class="acronym">SQL</acronym> Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/pltcl.html">44. PL/Tcl — Tcl Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/plperl.html">45. PL/Perl — Perl Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/plpython.html">46. PL/Python — Python Procedural Language</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/spi.html">47. Server Programming Interface</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/bgworker.html">48. Background Worker Processes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/logicaldecoding.html">49. Logical Decoding</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/replication-origins.html">50. Replication Progress Tracking</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/archive-modules.html">51. Archive Modules</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/reference.html">VI. Reference</a></span></dt>
<dd>
<dl>
<dt><span class="reference"><a href="/docs/16/sql-commands.html">I. SQL Commands</a></span></dt>
<dt><span class="reference"><a href="/docs/16/reference-client.html">II. PostgreSQL Client Applications</a></span></dt>
<dt><span class="reference"><a href="/docs/16/reference-server.html">III. PostgreSQL Server Applications</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/internals.html">VII. Internals</a></span></dt>
<dd>
<dl>
<dt><span class="chapter"><a href="/docs/16/overview.html">52. Overview of PostgreSQL Internals</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/catalogs.html">53. System Catalogs</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/views.html">54. System Views</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/protocol.html">55. Frontend/Backend Protocol</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/source.html">56. PostgreSQL Coding Conventions</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/nls.html">57. Native Language Support</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/plhandler.html">58. Writing a Procedural Language Handler</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/fdwhandler.html">59. Writing a Foreign Data Wrapper</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/tablesample-method.html">60. Writing a Table Sampling Method</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/custom-scan.html">61. Writing a Custom Scan Provider</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/geqo.html">62. Genetic Query Optimizer</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/tableam.html">63. Table Access Method Interface Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/indexam.html">64. Index Access Method Interface Definition</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/generic-wal.html">65. Generic WAL Records</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/custom-rmgr.html">66. Custom WAL Resource Managers</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/btree.html">67. B-Tree Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/gist.html">68. GiST Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/spgist.html">69. SP-GiST Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/gin.html">70. GIN Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/brin.html">71. BRIN Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/hash-index.html">72. Hash Indexes</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/storage.html">73. Database Physical Storage</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/transactions.html">74. Transaction Processing</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/bki.html">75. System Catalog Declarations and Initial Contents</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/planner-stats-details.html">76. How the Planner Uses Statistics</a></span></dt>
<dt><span class="chapter"><a href="/docs/16/backup-manifest-format.html">77. Backup Manifest Format</a></span></dt>
</dl>
</dd>
<dt><span class="part"><a href="/docs/16/appendixes.html">VIII. Appendixes</a></span></dt>
<dd>
<dl>
<dt><span class="appendix"><a href="/docs/16/errcodes-appendix.html">A. <span class="productname">PostgreSQL</span> Error Codes</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/datetime-appendix.html">B. Date/Time Support</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/sql-keywords-appendix.html">C. <acronym class="acronym">SQL</acronym> Key Words</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/features.html">D. SQL Conformance</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/release.html">E. Release Notes</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/contrib.html">F. Additional Supplied Modules and Extensions</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/contrib-prog.html">G. Additional Supplied Programs</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/external-projects.html">H. External Projects</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/sourcerepo.html">I. The Source Code Repository</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/docguide.html">J. Documentation</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/limits.html">K. <span class="productname">PostgreSQL</span> Limits</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/acronyms.html">L. Acronyms</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/glossary.html">M. Glossary</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/color.html">N. Color Support</a></span></dt>
<dt><span class="appendix"><a href="/docs/16/appendix-obsolete.html">O. Obsolete or Renamed Features</a></span></dt>
</dl>
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<dt><span class="bibliography"><a href="/docs/16/biblio.html">Bibliography</a></span></dt>
<dt><span class="index"><a href="/docs/16/bookindex.html">Index</a></span></dt>
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