<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>PostgreSQL 11.5 Documentation</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="next" href="preface.html" title="Preface" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">PostgreSQL 11.5 Documentation</th></tr><tr><td width="10%" align="left"> </td><td width="10%" align="left"> </td><th width="60%" align="center"> </th><td width="10%" align="right"> </td><td width="10%" align="right"> <a accesskey="n" href="preface.html" title="Preface">Next</a></td></tr></table><hr></hr></div><div class="book" id="POSTGRES"><div class="titlepage"><div><div><h1 class="title">PostgreSQL 11.5 Documentation</h1></div><div><h3 class="corpauthor">The PostgreSQL Global Development Group</h3></div><div><p class="copyright">Copyright © 1996-2019 The PostgreSQL Global Development Group</p></div><div><a href="legalnotice.html">Legal Notice</a></div></div><hr /></div><div class="toc"><p><strong>Table of Contents</strong></p><dl class="toc"><dt><span class="preface"><a href="preface.html">Preface</a></span></dt><dd><dl><dt><span class="sect1"><a href="intro-whatis.html">1. What is <span class="productname">PostgreSQL</span>?</a></span></dt><dt><span class="sect1"><a href="history.html">2. A Brief History of <span class="productname">PostgreSQL</span></a></span></dt><dt><span class="sect1"><a href="notation.html">3. Conventions</a></span></dt><dt><span class="sect1"><a href="resources.html">4. Further Information</a></span></dt><dt><span class="sect1"><a href="bug-reporting.html">5. Bug Reporting Guidelines</a></span></dt></dl></dd><dt><span class="part"><a href="tutorial.html">I. Tutorial</a></span></dt><dd><dl><dt><span class="chapter"><a href="tutorial-start.html">1. Getting Started</a></span></dt><dt><span class="chapter"><a href="tutorial-sql.html">2. The <acronym class="acronym">SQL</acronym> Language</a></span></dt><dt><span class="chapter"><a href="tutorial-advanced.html">3. Advanced Features</a></span></dt></dl></dd><dt><span class="part"><a href="sql.html">II. The SQL Language</a></span></dt><dd><dl><dt><span class="chapter"><a href="sql-syntax.html">4. SQL Syntax</a></span></dt><dt><span class="chapter"><a href="ddl.html">5. Data Definition</a></span></dt><dt><span class="chapter"><a href="dml.html">6. Data Manipulation</a></span></dt><dt><span class="chapter"><a href="queries.html">7. Queries</a></span></dt><dt><span class="chapter"><a href="datatype.html">8. Data Types</a></span></dt><dt><span class="chapter"><a href="functions.html">9. Functions and Operators</a></span></dt><dt><span class="chapter"><a href="typeconv.html">10. Type Conversion</a></span></dt><dt><span class="chapter"><a href="indexes.html">11. Indexes</a></span></dt><dt><span class="chapter"><a href="textsearch.html">12. Full Text Search</a></span></dt><dt><span class="chapter"><a href="mvcc.html">13. Concurrency Control</a></span></dt><dt><span class="chapter"><a href="performance-tips.html">14. Performance Tips</a></span></dt><dt><span class="chapter"><a href="parallel-query.html">15. Parallel Query</a></span></dt></dl></dd><dt><span class="part"><a href="admin.html">III. Server Administration</a></span></dt><dd><dl><dt><span class="chapter"><a href="installation.html">16. Installation from Source Code</a></span></dt><dt><span class="chapter"><a href="install-windows.html">17. Installation from Source Code on <span class="productname">Windows</span></a></span></dt><dt><span class="chapter"><a href="runtime.html">18. Server Setup and Operation</a></span></dt><dt><span class="chapter"><a href="runtime-config.html">19. Server Configuration</a></span></dt><dt><span class="chapter"><a href="client-authentication.html">20. Client Authentication</a></span></dt><dt><span class="chapter"><a href="user-manag.html">21. Database Roles</a></span></dt><dt><span class="chapter"><a href="managing-databases.html">22. Managing Databases</a></span></dt><dt><span class="chapter"><a href="charset.html">23. Localization</a></span></dt><dt><span class="chapter"><a href="maintenance.html">24. Routine Database Maintenance Tasks</a></span></dt><dt><span class="chapter"><a href="backup.html">25. Backup and Restore</a></span></dt><dt><span class="chapter"><a href="high-availability.html">26. High Availability, Load Balancing, and Replication</a></span></dt><dt><span class="chapter"><a href="recovery-config.html">27. Recovery Configuration</a></span></dt><dt><span class="chapter"><a href="monitoring.html">28. Monitoring Database Activity</a></span></dt><dt><span class="chapter"><a href="diskusage.html">29. Monitoring Disk Usage</a></span></dt><dt><span class="chapter"><a href="wal.html">30. Reliability and the Write-Ahead Log</a></span></dt><dt><span class="chapter"><a href="logical-replication.html">31. Logical Replication</a></span></dt><dt><span class="chapter"><a href="jit.html">32. Just-in-Time Compilation (<acronym class="acronym">JIT</acronym>)</a></span></dt><dt><span class="chapter"><a href="regress.html">33. Regression Tests</a></span></dt></dl></dd><dt><span class="part"><a href="client-interfaces.html">IV. Client Interfaces</a></span></dt><dd><dl><dt><span class="chapter"><a href="libpq.html">34. <span class="application">libpq</span> - C Library</a></span></dt><dt><span class="chapter"><a href="largeobjects.html">35. Large Objects</a></span></dt><dt><span class="chapter"><a href="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="information-schema.html">37. The Information Schema</a></span></dt></dl></dd><dt><span class="part"><a href="server-programming.html">V. Server Programming</a></span></dt><dd><dl><dt><span class="chapter"><a href="extend.html">38. Extending <acronym class="acronym">SQL</acronym></a></span></dt><dt><span class="chapter"><a href="triggers.html">39. Triggers</a></span></dt><dt><span class="chapter"><a href="event-triggers.html">40. Event Triggers</a></span></dt><dt><span class="chapter"><a href="rules.html">41. The Rule System</a></span></dt><dt><span class="chapter"><a href="xplang.html">42. Procedural Languages</a></span></dt><dt><span class="chapter"><a href="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="pltcl.html">44. PL/Tcl - Tcl Procedural Language</a></span></dt><dt><span class="chapter"><a href="plperl.html">45. PL/Perl - Perl Procedural Language</a></span></dt><dt><span class="chapter"><a href="plpython.html">46. PL/Python - Python Procedural Language</a></span></dt><dt><span class="chapter"><a href="spi.html">47. Server Programming Interface</a></span></dt><dt><span class="chapter"><a href="bgworker.html">48. Background Worker Processes</a></span></dt><dt><span class="chapter"><a href="logicaldecoding.html">49. Logical Decoding</a></span></dt><dt><span class="chapter"><a href="replication-origins.html">50. Replication Progress Tracking</a></span></dt></dl></dd><dt><span class="part"><a href="reference.html">VI. Reference</a></span></dt><dd><dl><dt><span class="reference"><a href="sql-commands.html">I. SQL Commands</a></span></dt><dt><span class="reference"><a href="reference-client.html">II. PostgreSQL Client Applications</a></span></dt><dt><span class="reference"><a href="reference-server.html">III. PostgreSQL Server Applications</a></span></dt></dl></dd><dt><span class="part"><a href="internals.html">VII. Internals</a></span></dt><dd><dl><dt><span class="chapter"><a href="overview.html">51. Overview of PostgreSQL Internals</a></span></dt><dt><span class="chapter"><a href="catalogs.html">52. System Catalogs</a></span></dt><dt><span class="chapter"><a href="protocol.html">53. Frontend/Backend Protocol</a></span></dt><dt><span class="chapter"><a href="source.html">54. PostgreSQL Coding Conventions</a></span></dt><dt><span class="chapter"><a href="nls.html">55. Native Language Support</a></span></dt><dt><span class="chapter"><a href="plhandler.html">56. Writing A Procedural Language Handler</a></span></dt><dt><span class="chapter"><a href="fdwhandler.html">57. Writing A Foreign Data Wrapper</a></span></dt><dt><span class="chapter"><a href="tablesample-method.html">58. Writing A Table Sampling Method</a></span></dt><dt><span class="chapter"><a href="custom-scan.html">59. Writing A Custom Scan Provider</a></span></dt><dt><span class="chapter"><a href="geqo.html">60. Genetic Query Optimizer</a></span></dt><dt><span class="chapter"><a href="indexam.html">61. Index Access Method Interface Definition</a></span></dt><dt><span class="chapter"><a href="generic-wal.html">62. Generic WAL Records</a></span></dt><dt><span class="chapter"><a href="btree.html">63. B-Tree Indexes</a></span></dt><dt><span class="chapter"><a href="gist.html">64. GiST Indexes</a></span></dt><dt><span class="chapter"><a href="spgist.html">65. SP-GiST Indexes</a></span></dt><dt><span class="chapter"><a href="gin.html">66. GIN Indexes</a></span></dt><dt><span class="chapter"><a href="brin.html">67. BRIN Indexes</a></span></dt><dt><span class="chapter"><a href="storage.html">68. Database Physical Storage</a></span></dt><dt><span class="chapter"><a href="bki.html">69. System Catalog Declarations and Initial Contents</a></span></dt><dt><span class="chapter"><a href="planner-stats-details.html">70. How the Planner Uses Statistics</a></span></dt></dl></dd><dt><span class="part"><a href="appendixes.html">VIII. Appendixes</a></span></dt><dd><dl><dt><span class="appendix"><a href="errcodes-appendix.html">A. <span class="productname">PostgreSQL</span> Error Codes</a></span></dt><dt><span class="appendix"><a href="datetime-appendix.html">B. Date/Time Support</a></span></dt><dt><span class="appendix"><a href="sql-keywords-appendix.html">C. <acronym class="acronym">SQL</acronym> Key Words</a></span></dt><dt><span class="appendix"><a href="features.html">D. SQL Conformance</a></span></dt><dt><span class="appendix"><a href="release.html">E. Release Notes</a></span></dt><dt><span class="appendix"><a href="contrib.html">F. Additional Supplied Modules</a></span></dt><dt><span class="appendix"><a href="contrib-prog.html">G. Additional Supplied Programs</a></span></dt><dt><span class="appendix"><a href="external-projects.html">H. External Projects</a></span></dt><dt><span class="appendix"><a href="sourcerepo.html">I. The Source Code Repository</a></span></dt><dt><span class="appendix"><a href="docguide.html">J. Documentation</a></span></dt><dt><span class="appendix"><a href="acronyms.html">K. Acronyms</a></span></dt></dl></dd><dt><span class="bibliography"><a href="biblio.html">Bibliography</a></span></dt><dt><span class="index"><a href="bookindex.html">Index</a></span></dt></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="preface.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"> </td><td width="20%" align="center"> </td><td width="40%" align="right" valign="top"> Preface</td></tr></table></div></body></html>
