summaryrefslogtreecommitdiffstats
path: root/doc/src/sgml/html/sql-createdatabase.html
blob: 27277e2f8add351c527b981b5d6d914e7a919874 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
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 15.6 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 15.6 Documentation">Home</a></td><td width="40%" align="right" valign="top"> CREATE DOMAIN</td></tr></table></div></body></html>