<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >The Information Schema</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 8.0.11 Documentation" HREF="index.html"><LINK REL="UP" TITLE="Client Interfaces" HREF="client-interfaces.html"><LINK REL="PREVIOUS" TITLE="Internals" HREF="ecpg-develop.html"><LINK REL="NEXT" TITLE="Data Types" HREF="infoschema-datatypes.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2007-02-02T03:57:22"></HEAD ><BODY CLASS="CHAPTER" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" >PostgreSQL 8.0.11 Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="ecpg-develop.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="ecpg.html" >Fast Backward</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="top" ><A HREF="server-programming.html" >Fast Forward</A ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="top" ><A HREF="infoschema-datatypes.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="INFORMATION-SCHEMA" ></A >Chapter 30. The Information Schema</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT >30.1. <A HREF="information-schema.html#INFOSCHEMA-SCHEMA" >The Schema</A ></DT ><DT >30.2. <A HREF="infoschema-datatypes.html" >Data Types</A ></DT ><DT >30.3. <A HREF="infoschema-information-schema-catalog-name.html" ><TT CLASS="LITERAL" >information_schema_catalog_name</TT ></A ></DT ><DT >30.4. <A HREF="infoschema-applicable-roles.html" ><TT CLASS="LITERAL" >applicable_roles</TT ></A ></DT ><DT >30.5. <A HREF="infoschema-check-constraints.html" ><TT CLASS="LITERAL" >check_constraints</TT ></A ></DT ><DT >30.6. <A HREF="infoschema-column-domain-usage.html" ><TT CLASS="LITERAL" >column_domain_usage</TT ></A ></DT ><DT >30.7. <A HREF="infoschema-column-privileges.html" ><TT CLASS="LITERAL" >column_privileges</TT ></A ></DT ><DT >30.8. <A HREF="infoschema-column-udt-usage.html" ><TT CLASS="LITERAL" >column_udt_usage</TT ></A ></DT ><DT >30.9. <A HREF="infoschema-columns.html" ><TT CLASS="LITERAL" >columns</TT ></A ></DT ><DT >30.10. <A HREF="infoschema-constraint-column-usage.html" ><TT CLASS="LITERAL" >constraint_column_usage</TT ></A ></DT ><DT >30.11. <A HREF="infoschema-constraint-table-usage.html" ><TT CLASS="LITERAL" >constraint_table_usage</TT ></A ></DT ><DT >30.12. <A HREF="infoschema-data-type-privileges.html" ><TT CLASS="LITERAL" >data_type_privileges</TT ></A ></DT ><DT >30.13. <A HREF="infoschema-domain-constraints.html" ><TT CLASS="LITERAL" >domain_constraints</TT ></A ></DT ><DT >30.14. <A HREF="infoschema-domain-udt-usage.html" ><TT CLASS="LITERAL" >domain_udt_usage</TT ></A ></DT ><DT >30.15. <A HREF="infoschema-domains.html" ><TT CLASS="LITERAL" >domains</TT ></A ></DT ><DT >30.16. <A HREF="infoschema-element-types.html" ><TT CLASS="LITERAL" >element_types</TT ></A ></DT ><DT >30.17. <A HREF="infoschema-enabled-roles.html" ><TT CLASS="LITERAL" >enabled_roles</TT ></A ></DT ><DT >30.18. <A HREF="infoschema-key-column-usage.html" ><TT CLASS="LITERAL" >key_column_usage</TT ></A ></DT ><DT >30.19. <A HREF="infoschema-parameters.html" ><TT CLASS="LITERAL" >parameters</TT ></A ></DT ><DT >30.20. <A HREF="infoschema-referential-constraints.html" ><TT CLASS="LITERAL" >referential_constraints</TT ></A ></DT ><DT >30.21. <A HREF="infoschema-role-column-grants.html" ><TT CLASS="LITERAL" >role_column_grants</TT ></A ></DT ><DT >30.22. <A HREF="infoschema-role-routine-grants.html" ><TT CLASS="LITERAL" >role_routine_grants</TT ></A ></DT ><DT >30.23. <A HREF="infoschema-role-table-grants.html" ><TT CLASS="LITERAL" >role_table_grants</TT ></A ></DT ><DT >30.24. <A HREF="infoschema-role-usage-grants.html" ><TT CLASS="LITERAL" >role_usage_grants</TT ></A ></DT ><DT >30.25. <A HREF="infoschema-routine-privileges.html" ><TT CLASS="LITERAL" >routine_privileges</TT ></A ></DT ><DT >30.26. <A HREF="infoschema-routines.html" ><TT CLASS="LITERAL" >routines</TT ></A ></DT ><DT >30.27. <A HREF="infoschema-schemata.html" ><TT CLASS="LITERAL" >schemata</TT ></A ></DT ><DT >30.28. <A HREF="infoschema-sql-features.html" ><TT CLASS="LITERAL" >sql_features</TT ></A ></DT ><DT >30.29. <A HREF="infoschema-sql-implementation-info.html" ><TT CLASS="LITERAL" >sql_implementation_info</TT ></A ></DT ><DT >30.30. <A HREF="infoschema-sql-languages.html" ><TT CLASS="LITERAL" >sql_languages</TT ></A ></DT ><DT >30.31. <A HREF="infoschema-sql-packages.html" ><TT CLASS="LITERAL" >sql_packages</TT ></A ></DT ><DT >30.32. <A HREF="infoschema-sql-sizing.html" ><TT CLASS="LITERAL" >sql_sizing</TT ></A ></DT ><DT >30.33. <A HREF="infoschema-sql-sizing-profiles.html" ><TT CLASS="LITERAL" >sql_sizing_profiles</TT ></A ></DT ><DT >30.34. <A HREF="infoschema-table-constraints.html" ><TT CLASS="LITERAL" >table_constraints</TT ></A ></DT ><DT >30.35. <A HREF="infoschema-table-privileges.html" ><TT CLASS="LITERAL" >table_privileges</TT ></A ></DT ><DT >30.36. <A HREF="infoschema-tables.html" ><TT CLASS="LITERAL" >tables</TT ></A ></DT ><DT >30.37. <A HREF="infoschema-triggers.html" ><TT CLASS="LITERAL" >triggers</TT ></A ></DT ><DT >30.38. <A HREF="infoschema-usage-privileges.html" ><TT CLASS="LITERAL" >usage_privileges</TT ></A ></DT ><DT >30.39. <A HREF="infoschema-view-column-usage.html" ><TT CLASS="LITERAL" >view_column_usage</TT ></A ></DT ><DT >30.40. <A HREF="infoschema-view-table-usage.html" ><TT CLASS="LITERAL" >view_table_usage</TT ></A ></DT ><DT >30.41. <A HREF="infoschema-views.html" ><TT CLASS="LITERAL" >views</TT ></A ></DT ></DL ></DIV ><A NAME="AEN25933" ></A ><P > The information schema consists of a set of views that contain information about the objects defined in the current database. The information schema is defined in the SQL standard and can therefore be expected to be portable and remain stable — unlike the system catalogs, which are specific to <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > and are modelled after implementation concerns. The information schema views do not, however, contain information about <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >-specific features; to inquire about those you need to query the system catalogs or other <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >-specific views. </P ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="INFOSCHEMA-SCHEMA" >30.1. The Schema</A ></H1 ><P > The information schema itself is a schema named <TT CLASS="LITERAL" >information_schema</TT >. This schema automatically exists in all databases. The owner of this schema is the initial database user in the cluster, and that user naturally has all the privileges on this schema, including the ability to drop it (but the space savings achieved by that are minuscule). </P ><P > By default, the information schema is not in the schema search path, so you need to access all objects in it through qualified names. Since the names of some of the objects in the information schema are generic names that might occur in user applications, you should be careful if you want to put the information schema in the path. </P ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="ecpg-develop.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="infoschema-datatypes.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Internals</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="client-interfaces.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Data Types</TD ></TR ></TABLE ></DIV ></BODY ></HTML >