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diff --git a/doc/src/sgml/html/sql-createdatabase.html b/doc/src/sgml/html/sql-createdatabase.html new file mode 100644 index 0000000..0f04e76 --- /dev/null +++ b/doc/src/sgml/html/sql-createdatabase.html @@ -0,0 +1,240 @@ +<?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>CREATE DATABASE</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="prev" href="sql-createconversion.html" title="CREATE CONVERSION" /><link rel="next" href="sql-createdomain.html" title="CREATE DOMAIN" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">CREATE DATABASE</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-createconversion.html" title="CREATE CONVERSION">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-createdomain.html" title="CREATE DOMAIN">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-CREATEDATABASE"><div class="titlepage"></div><a id="id-1.9.3.61.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">CREATE DATABASE</span></h2><p>CREATE DATABASE — create a new database</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +CREATE DATABASE <em class="replaceable"><code>name</code></em> + [ WITH ] [ OWNER [=] <em class="replaceable"><code>user_name</code></em> ] + [ TEMPLATE [=] <em class="replaceable"><code>template</code></em> ] + [ ENCODING [=] <em class="replaceable"><code>encoding</code></em> ] + [ STRATEGY [=] <em class="replaceable"><code>strategy</code></em> ] ] + [ LOCALE [=] <em class="replaceable"><code>locale</code></em> ] + [ LC_COLLATE [=] <em class="replaceable"><code>lc_collate</code></em> ] + [ LC_CTYPE [=] <em class="replaceable"><code>lc_ctype</code></em> ] + [ ICU_LOCALE [=] <em class="replaceable"><code>icu_locale</code></em> ] + [ LOCALE_PROVIDER [=] <em class="replaceable"><code>locale_provider</code></em> ] + [ COLLATION_VERSION = <em class="replaceable"><code>collation_version</code></em> ] + [ TABLESPACE [=] <em class="replaceable"><code>tablespace_name</code></em> ] + [ ALLOW_CONNECTIONS [=] <em class="replaceable"><code>allowconn</code></em> ] + [ CONNECTION LIMIT [=] <em class="replaceable"><code>connlimit</code></em> ] + [ IS_TEMPLATE [=] <em class="replaceable"><code>istemplate</code></em> ] + [ OID [=] <em class="replaceable"><code>oid</code></em> ] +</pre></div><div class="refsect1" id="id-1.9.3.61.5"><h2>Description</h2><p> + <code class="command">CREATE DATABASE</code> creates a new + <span class="productname">PostgreSQL</span> database. + </p><p> + To create a database, you must be a superuser or have the special + <code class="literal">CREATEDB</code> privilege. + See <a class="xref" href="sql-createrole.html" title="CREATE ROLE"><span class="refentrytitle">CREATE ROLE</span></a>. + </p><p> + By default, the new database will be created by cloning the standard + system database <code class="literal">template1</code>. A different template can be + specified by writing <code class="literal">TEMPLATE + <em class="replaceable"><code>name</code></em></code>. In particular, + by writing <code class="literal">TEMPLATE template0</code>, you can create a pristine + database (one where no user-defined objects exist and where the system + objects have not been altered) + containing only the standard objects predefined by your + version of <span class="productname">PostgreSQL</span>. This is useful + if you wish to avoid copying + any installation-local objects that might have been added to + <code class="literal">template1</code>. + </p></div><div class="refsect1" id="id-1.9.3.61.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p> + The name of a database to create. + </p></dd><dt><span class="term"><em class="replaceable"><code>user_name</code></em></span></dt><dd><p> + The role name of the user who will own the new database, + or <code class="literal">DEFAULT</code> to use the default (namely, the + user executing the command). To create a database owned by another + role, you must be a direct or indirect member of that role, + or be a superuser. + </p></dd><dt><span class="term"><em class="replaceable"><code>template</code></em></span></dt><dd><p> + The name of the template from which to create the new database, + or <code class="literal">DEFAULT</code> to use the default template + (<code class="literal">template1</code>). + </p></dd><dt><span class="term"><em class="replaceable"><code>encoding</code></em></span></dt><dd><p> + Character set encoding to use in the new database. Specify + a string constant (e.g., <code class="literal">'SQL_ASCII'</code>), + or an integer encoding number, or <code class="literal">DEFAULT</code> + to use the default encoding (namely, the encoding of the + template database). The character sets supported by the + <span class="productname">PostgreSQL</span> server are described in + <a class="xref" href="multibyte.html#MULTIBYTE-CHARSET-SUPPORTED" title="24.3.1. Supported Character Sets">Section 24.3.1</a>. See below for + additional restrictions. + </p></dd><dt id="CREATE-DATABASE-STRATEGY"><span class="term"><em class="replaceable"><code>strategy</code></em></span></dt><dd><p> + Strategy to be used in creating the new database. If + the <code class="literal">WAL_LOG</code> strategy is used, the database will be + copied block by block and each block will be separately written + to the write-ahead log. This is the most efficient strategy in + cases where the template database is small, and therefore it is the + default. The older <code class="literal">FILE_COPY</code> strategy is also + available. This strategy writes a small record to the write-ahead log + for each tablespace used by the target database. Each such record + represents copying an entire directory to a new location at the + filesystem level. While this does reduce the write-ahead + log volume substantially, especially if the template database is large, + it also forces the system to perform a checkpoint both before and + after the creation of the new database. In some situations, this may + have a noticeable negative impact on overall system performance. + </p></dd><dt><span class="term"><em class="replaceable"><code>locale</code></em></span></dt><dd><p> + This is a shortcut for setting <code class="symbol">LC_COLLATE</code> + and <code class="symbol">LC_CTYPE</code> at once. + </p><div class="tip"><h3 class="title">Tip</h3><p> + The other locale settings <a class="xref" href="runtime-config-client.html#GUC-LC-MESSAGES">lc_messages</a>, <a class="xref" href="runtime-config-client.html#GUC-LC-MONETARY">lc_monetary</a>, <a class="xref" href="runtime-config-client.html#GUC-LC-NUMERIC">lc_numeric</a>, and + <a class="xref" href="runtime-config-client.html#GUC-LC-TIME">lc_time</a> are not fixed per database and are not + set by this command. If you want to make them the default for a + specific database, you can use <code class="literal">ALTER DATABASE + ... SET</code>. + </p></div></dd><dt><span class="term"><em class="replaceable"><code>lc_collate</code></em></span></dt><dd><p> + Collation order (<code class="literal">LC_COLLATE</code>) to use in the new database. + This affects the sort order applied to strings, e.g., in queries with + ORDER BY, as well as the order used in indexes on text columns. + The default is to use the collation order of the template database. + See below for additional restrictions. + </p></dd><dt><span class="term"><em class="replaceable"><code>lc_ctype</code></em></span></dt><dd><p> + Character classification (<code class="literal">LC_CTYPE</code>) to use in the new + database. This affects the categorization of characters, e.g., lower, + upper and digit. The default is to use the character classification of + the template database. See below for additional restrictions. + </p></dd><dt><span class="term"><em class="replaceable"><code>icu_locale</code></em></span></dt><dd><p> + Specifies the ICU locale ID if the ICU locale provider is used. + </p></dd><dt><span class="term"><em class="replaceable"><code>locale_provider</code></em></span></dt><dd><p> + Specifies the provider to use for the default collation in this + database. Possible values are: + <code class="literal">icu</code>,<a id="id-1.9.3.61.6.2.10.2.1.2" class="indexterm"></a> + <code class="literal">libc</code>. <code class="literal">libc</code> is the default. The + available choices depend on the operating system and build options. + </p></dd><dt><span class="term"><em class="replaceable"><code>collation_version</code></em></span></dt><dd><p> + Specifies the collation version string to store with the database. + Normally, this should be omitted, which will cause the version to be + computed from the actual version of the database collation as provided + by the operating system. This option is intended to be used by + <code class="command">pg_upgrade</code> for copying the version from an existing + installation. + </p><p> + See also <a class="xref" href="sql-alterdatabase.html" title="ALTER DATABASE"><span class="refentrytitle">ALTER DATABASE</span></a> for how to handle + database collation version mismatches. + </p></dd><dt><span class="term"><em class="replaceable"><code>tablespace_name</code></em></span></dt><dd><p> + The name of the tablespace that will be associated with the + new database, or <code class="literal">DEFAULT</code> to use the + template database's tablespace. This + tablespace will be the default tablespace used for objects + created in this database. See + <a class="xref" href="sql-createtablespace.html" title="CREATE TABLESPACE"><span class="refentrytitle">CREATE TABLESPACE</span></a> + for more information. + </p></dd><dt><span class="term"><em class="replaceable"><code>allowconn</code></em></span></dt><dd><p> + If false then no one can connect to this database. The default is + true, allowing connections (except as restricted by other mechanisms, + such as <code class="literal">GRANT</code>/<code class="literal">REVOKE CONNECT</code>). + </p></dd><dt><span class="term"><em class="replaceable"><code>connlimit</code></em></span></dt><dd><p> + How many concurrent connections can be made + to this database. -1 (the default) means no limit. + </p></dd><dt><span class="term"><em class="replaceable"><code>istemplate</code></em></span></dt><dd><p> + If true, then this database can be cloned by any user with <code class="literal">CREATEDB</code> + privileges; if false (the default), then only superusers or the owner + of the database can clone it. + </p></dd><dt><span class="term"><em class="replaceable"><code>oid</code></em></span></dt><dd><p> + The object identifier to be used for the new database. If this + parameter is not specified, <span class="productname">PostgreSQL</span> + will choose a suitable OID automatically. This parameter is primarily + intended for internal use by <span class="application">pg_upgrade</span>, + and only <span class="application">pg_upgrade</span> can specify a value + less than 16384. + </p></dd></dl></div><p> + Optional parameters can be written in any order, not only the order + illustrated above. + </p></div><div class="refsect1" id="id-1.9.3.61.7"><h2>Notes</h2><p> + <code class="command">CREATE DATABASE</code> cannot be executed inside a transaction + block. + </p><p> + Errors along the line of <span class="quote">“<span class="quote">could not initialize database directory</span>”</span> + are most likely related to insufficient permissions on the data + directory, a full disk, or other file system problems. + </p><p> + Use <a class="link" href="sql-dropdatabase.html" title="DROP DATABASE"><code class="command">DROP DATABASE</code></a> to remove a database. + </p><p> + The program <a class="xref" href="app-createdb.html" title="createdb"><span class="refentrytitle"><span class="application">createdb</span></span></a> is a + wrapper program around this command, provided for convenience. + </p><p> + Database-level configuration parameters (set via <a class="link" href="sql-alterdatabase.html" title="ALTER DATABASE"><code class="command">ALTER DATABASE</code></a>) and database-level permissions (set via + <a class="link" href="sql-grant.html" title="GRANT"><code class="command">GRANT</code></a>) are not copied from the template database. + </p><p> + Although it is possible to copy a database other than <code class="literal">template1</code> + by specifying its name as the template, this is not (yet) intended as + a general-purpose <span class="quote">“<span class="quote"><code class="command">COPY DATABASE</code></span>”</span> facility. + The principal limitation is that no other sessions can be connected to + the template database while it is being copied. <code class="command">CREATE + DATABASE</code> will fail if any other connection exists when it starts; + otherwise, new connections to the template database are locked out + until <code class="command">CREATE DATABASE</code> completes. + See <a class="xref" href="manage-ag-templatedbs.html" title="23.3. Template Databases">Section 23.3</a> for more information. + </p><p> + The character set encoding specified for the new database must be + compatible with the chosen locale settings (<code class="literal">LC_COLLATE</code> and + <code class="literal">LC_CTYPE</code>). If the locale is <code class="literal">C</code> (or equivalently + <code class="literal">POSIX</code>), then all encodings are allowed, but for other + locale settings there is only one encoding that will work properly. + (On Windows, however, UTF-8 encoding can be used with any locale.) + <code class="command">CREATE DATABASE</code> will allow superusers to specify + <code class="literal">SQL_ASCII</code> encoding regardless of the locale settings, + but this choice is deprecated and may result in misbehavior of + character-string functions if data that is not encoding-compatible + with the locale is stored in the database. + </p><p> + The encoding and locale settings must match those of the template database, + except when <code class="literal">template0</code> is used as template. This is because + other databases might contain data that does not match the specified + encoding, or might contain indexes whose sort ordering is affected by + <code class="literal">LC_COLLATE</code> and <code class="literal">LC_CTYPE</code>. Copying such data would + result in a database that is corrupt according to the new settings. + <code class="literal">template0</code>, however, is known to not contain any data or + indexes that would be affected. + </p><p> + There is currently no option to use a database locale with nondeterministic + comparisons (see <a class="link" href="sql-createcollation.html" title="CREATE COLLATION"><code class="command">CREATE + COLLATION</code></a> for an explanation). If this is needed, then + per-column collations would need to be used. + </p><p> + The <code class="literal">CONNECTION LIMIT</code> option is only enforced approximately; + if two new sessions start at about the same time when just one + connection <span class="quote">“<span class="quote">slot</span>”</span> remains for the database, it is possible that + both will fail. Also, the limit is not enforced against superusers or + background worker processes. + </p></div><div class="refsect1" id="id-1.9.3.61.8"><h2>Examples</h2><p> + To create a new database: + +</p><pre class="programlisting"> +CREATE DATABASE lusiadas; +</pre><p> + </p><p> + To create a database <code class="literal">sales</code> owned by user <code class="literal">salesapp</code> + with a default tablespace of <code class="literal">salesspace</code>: + +</p><pre class="programlisting"> +CREATE DATABASE sales OWNER salesapp TABLESPACE salesspace; +</pre><p> + </p><p> + To create a database <code class="literal">music</code> with a different locale: +</p><pre class="programlisting"> +CREATE DATABASE music + LOCALE 'sv_SE.utf8' + TEMPLATE template0; +</pre><p> + In this example, the <code class="literal">TEMPLATE template0</code> clause is required if + the specified locale is different from the one in <code class="literal">template1</code>. + (If it is not, then specifying the locale explicitly is redundant.) + </p><p> + To create a database <code class="literal">music2</code> with a different locale and a + different character set encoding: +</p><pre class="programlisting"> +CREATE DATABASE music2 + LOCALE 'sv_SE.iso885915' + ENCODING LATIN9 + TEMPLATE template0; +</pre><p> + The specified locale and encoding settings must match, or an error will be + reported. + </p><p> + Note that locale names are specific to the operating system, so that the + above commands might not work in the same way everywhere. + </p></div><div class="refsect1" id="id-1.9.3.61.9"><h2>Compatibility</h2><p> + There is no <code class="command">CREATE DATABASE</code> statement in the SQL + standard. Databases are equivalent to catalogs, whose creation is + implementation-defined. + </p></div><div class="refsect1" id="id-1.9.3.61.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-alterdatabase.html" title="ALTER DATABASE"><span class="refentrytitle">ALTER DATABASE</span></a>, <a class="xref" href="sql-dropdatabase.html" title="DROP DATABASE"><span class="refentrytitle">DROP DATABASE</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-createconversion.html" title="CREATE CONVERSION">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-createdomain.html" title="CREATE DOMAIN">Next</a></td></tr><tr><td width="40%" align="left" valign="top">CREATE CONVERSION </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> CREATE DOMAIN</td></tr></table></div></body></html>
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