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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Creating a Database</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 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="Managing Databases" HREF="managing-databases.html"><LINK REL="PREVIOUS" TITLE="Overview" HREF="manage-ag-overview.html"><LINK REL="NEXT" TITLE="Template Databases" HREF="manage-ag-templatedbs.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="2017-11-06T22:43:11"></HEAD ><BODY CLASS="SECT1" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="Overview" HREF="manage-ag-overview.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="managing-databases.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Chapter 21. Managing Databases</TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="Template Databases" HREF="manage-ag-templatedbs.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="MANAGE-AG-CREATEDB" >21.2. Creating a Database</A ></H1 ><P > In order to create a database, the <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > server must be up and running (see <A HREF="server-start.html" >Section 17.3</A >). </P ><P > Databases are created with the SQL command <A HREF="sql-createdatabase.html" >CREATE DATABASE</A >: </P><PRE CLASS="SYNOPSIS" >CREATE DATABASE <TT CLASS="REPLACEABLE" ><I >name</I ></TT >;</PRE ><P> where <TT CLASS="REPLACEABLE" ><I >name</I ></TT > follows the usual rules for <ACRONYM CLASS="ACRONYM" >SQL</ACRONYM > identifiers. The current role automatically becomes the owner of the new database. It is the privilege of the owner of a database to remove it later (which also removes all the objects in it, even if they have a different owner). </P ><P > The creation of databases is a restricted operation. See <A HREF="role-attributes.html" >Section 20.2</A > for how to grant permission. </P ><P > Since you need to be connected to the database server in order to execute the <TT CLASS="COMMAND" >CREATE DATABASE</TT > command, the question remains how the <SPAN CLASS="emphasis" ><I CLASS="EMPHASIS" >first</I ></SPAN > database at any given site can be created. The first database is always created by the <TT CLASS="COMMAND" >initdb</TT > command when the data storage area is initialized. (See <A HREF="creating-cluster.html" >Section 17.2</A >.) This database is called <TT CLASS="LITERAL" >postgres</TT >. So to create the first <SPAN CLASS="QUOTE" >"ordinary"</SPAN > database you can connect to <TT CLASS="LITERAL" >postgres</TT >. </P ><P > A second database, <TT CLASS="LITERAL" >template1</TT >, is also created during database cluster initialization. Whenever a new database is created within the cluster, <TT CLASS="LITERAL" >template1</TT > is essentially cloned. This means that any changes you make in <TT CLASS="LITERAL" >template1</TT > are propagated to all subsequently created databases. Because of this, avoid creating objects in <TT CLASS="LITERAL" >template1</TT > unless you want them propagated to every newly created database. More details appear in <A HREF="manage-ag-templatedbs.html" >Section 21.3</A >. </P ><P > As a convenience, there is a program you can execute from the shell to create new databases, <TT CLASS="COMMAND" >createdb</TT >. </P><PRE CLASS="SYNOPSIS" >createdb <TT CLASS="REPLACEABLE" ><I >dbname</I ></TT ></PRE ><P> <TT CLASS="COMMAND" >createdb</TT > does no magic. It connects to the <TT CLASS="LITERAL" >postgres</TT > database and issues the <TT CLASS="COMMAND" >CREATE DATABASE</TT > command, exactly as described above. The <A HREF="app-createdb.html" ><SPAN CLASS="APPLICATION" >createdb</SPAN ></A > reference page contains the invocation details. Note that <TT CLASS="COMMAND" >createdb</TT > without any arguments will create a database with the current user name. </P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B > <A HREF="client-authentication.html" >Chapter 19</A > contains information about how to restrict who can connect to a given database. </P ></BLOCKQUOTE ></DIV ><P > Sometimes you want to create a database for someone else, and have him become the owner of the new database, so he can configure and manage it himself. To achieve that, use one of the following commands: </P><PRE CLASS="PROGRAMLISTING" >CREATE DATABASE <TT CLASS="REPLACEABLE" ><I >dbname</I ></TT > OWNER <TT CLASS="REPLACEABLE" ><I >rolename</I ></TT >;</PRE ><P> from the SQL environment, or: </P><PRE CLASS="PROGRAMLISTING" >createdb -O <TT CLASS="REPLACEABLE" ><I >rolename</I ></TT > <TT CLASS="REPLACEABLE" ><I >dbname</I ></TT ></PRE ><P> from the shell. Only the superuser is allowed to create a database for someone else (that is, for a role you are not a member of). </P ></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="manage-ag-overview.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="manage-ag-templatedbs.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Overview</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="managing-databases.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Template Databases</TD ></TR ></TABLE ></DIV ></BODY ></HTML >