Baoding-FenShuaJiang
/
Green_GoodERP18_FSJ_Standard
關注 1
收藏 0
Wiki 捐赠
gooderp18绿色标准版
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
分支: master
分支列表 標籤
${ item.name }
建立分支 ${ searchTerm }
從 'master'
${ noResults }
Green_GoodERP18_FSJ_Standard/PostgreSQL/doc/postgresql/html/sql-createschema.html

117 line
9.4KB
原始文件 永久連結 Blame 歷史記錄 

  1. <?xml version="1.0" encoding="UTF-8" standalone="no"?>

  2. <!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 SCHEMA</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 V1.79.1" /><link rel="prev" href="sql-createrule.html" title="CREATE RULE" /><link rel="next" href="sql-createsequence.html" title="CREATE SEQUENCE" /></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">CREATE SCHEMA</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-createrule.html" title="CREATE RULE">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 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-createsequence.html" title="CREATE SEQUENCE">Next</a></td></tr></table><hr></hr></div><div class="refentry" id="SQL-CREATESCHEMA"><div class="titlepage"></div><a id="id-1.9.3.80.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">CREATE SCHEMA</span></h2><p>CREATE SCHEMA — define a new schema</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">

  3. CREATE SCHEMA <em class="replaceable"><code>schema_name</code></em> [ AUTHORIZATION <em class="replaceable"><code>role_specification</code></em> ] [ <em class="replaceable"><code>schema_element</code></em> [ ... ] ]

  4. CREATE SCHEMA AUTHORIZATION <em class="replaceable"><code>role_specification</code></em> [ <em class="replaceable"><code>schema_element</code></em> [ ... ] ]

  5. CREATE SCHEMA IF NOT EXISTS <em class="replaceable"><code>schema_name</code></em> [ AUTHORIZATION <em class="replaceable"><code>role_specification</code></em> ]

  6. CREATE SCHEMA IF NOT EXISTS AUTHORIZATION <em class="replaceable"><code>role_specification</code></em>

  7. 

  8. <span class="phrase">where <em class="replaceable"><code>role_specification</code></em> can be:</span>

  9. 

  10.     <em class="replaceable"><code>user_name</code></em>

  11.   | CURRENT_USER

  12.   | SESSION_USER

  13. </pre></div><div class="refsect1" id="id-1.9.3.80.5"><h2>Description</h2><p>

  14.    <code class="command">CREATE SCHEMA</code> enters a new schema

  15.    into the current database.

  16.    The schema name must be distinct from the name of any existing schema

  17.    in the current database.

  18.   </p><p>

  19.    A schema is essentially a namespace:

  20.    it contains named objects (tables, data types, functions, and operators)

  21.    whose names can duplicate those of other objects existing in other

  22.    schemas.  Named objects are accessed either by <span class="quote">“<span class="quote">qualifying</span>”</span>

  23.    their names with the schema name as a prefix, or by setting a search

  24.    path that includes the desired schema(s).  A <code class="literal">CREATE</code> command

  25.    specifying an unqualified object name creates the object

  26.    in the current schema (the one at the front of the search path,

  27.    which can be determined with the function <code class="function">current_schema</code>).

  28.   </p><p>

  29.    Optionally, <code class="command">CREATE SCHEMA</code> can include subcommands

  30.    to create objects within the new schema.  The subcommands are treated

  31.    essentially the same as separate commands issued after creating the

  32.    schema, except that if the <code class="literal">AUTHORIZATION</code> clause is used,

  33.    all the created objects will be owned by that user.

  34.   </p></div><div class="refsect1" id="id-1.9.3.80.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>schema_name</code></em></span></dt><dd><p>

  35.         The name of a schema to be created.  If this is omitted, the

  36.         <em class="replaceable"><code>user_name</code></em>

  37.         is used as the schema name.  The name cannot

  38.         begin with <code class="literal">pg_</code>, as such names

  39.         are reserved for system schemas.

  40.        </p></dd><dt><span class="term"><em class="replaceable"><code>user_name</code></em></span></dt><dd><p>

  41.         The role name of the user who will own the new schema.  If omitted,

  42.         defaults to the user executing the command.  To create a schema

  43.         owned by another role, you must be a direct or indirect member of

  44.         that role, or be a superuser.

  45.        </p></dd><dt><span class="term"><em class="replaceable"><code>schema_element</code></em></span></dt><dd><p>

  46.         An SQL statement defining an object to be created within the

  47.         schema. Currently, only <code class="command">CREATE

  48.         TABLE</code>, <code class="command">CREATE VIEW</code>, <code class="command">CREATE

  49.         INDEX</code>, <code class="command">CREATE SEQUENCE</code>, <code class="command">CREATE

  50.         TRIGGER</code> and <code class="command">GRANT</code> are accepted as clauses

  51.         within <code class="command">CREATE SCHEMA</code>. Other kinds of objects may

  52.         be created in separate commands after the schema is created.

  53.        </p></dd><dt><span class="term"><code class="literal">IF NOT EXISTS</code></span></dt><dd><p>

  54.         Do nothing (except issuing a notice) if a schema with the same name

  55.         already exists.  <em class="replaceable"><code>schema_element</code></em>

  56.         subcommands cannot be included when this option is used.

  57.        </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.80.7"><h2>Notes</h2><p>

  58.    To create a schema, the invoking user must have the

  59.    <code class="literal">CREATE</code> privilege for the current database.

  60.    (Of course, superusers bypass this check.)

  61.   </p></div><div class="refsect1" id="id-1.9.3.80.8"><h2>Examples</h2><p>

  62.    Create a schema:

  63. </p><pre class="programlisting">

  64. CREATE SCHEMA myschema;

  65. </pre><p>

  66.   </p><p>

  67.    Create a schema for user <code class="literal">joe</code>; the schema will also be

  68.    named <code class="literal">joe</code>:

  69. </p><pre class="programlisting">

  70. CREATE SCHEMA AUTHORIZATION joe;

  71. </pre><p>

  72.   </p><p>

  73.    Create a schema named <code class="literal">test</code> that will be owned by user

  74.    <code class="literal">joe</code>, unless there already is a schema named <code class="literal">test</code>.

  75.    (It does not matter whether <code class="literal">joe</code> owns the pre-existing schema.)

  76. </p><pre class="programlisting">

  77. CREATE SCHEMA IF NOT EXISTS test AUTHORIZATION joe;

  78. </pre><p>

  79.   </p><p>

  80.    Create a schema and create a table and view within it:

  81. </p><pre class="programlisting">

  82. CREATE SCHEMA hollywood

  83.     CREATE TABLE films (title text, release date, awards text[])

  84.     CREATE VIEW winners AS

  85.         SELECT title, release FROM films WHERE awards IS NOT NULL;

  86. </pre><p>

  87.    Notice that the individual subcommands do not end with semicolons.

  88.   </p><p>

  89.    The following is an equivalent way of accomplishing the same result:

  90. </p><pre class="programlisting">

  91. CREATE SCHEMA hollywood;

  92. CREATE TABLE hollywood.films (title text, release date, awards text[]);

  93. CREATE VIEW hollywood.winners AS

  94.     SELECT title, release FROM hollywood.films WHERE awards IS NOT NULL;

  95. </pre></div><div class="refsect1" id="id-1.9.3.80.9"><h2>Compatibility</h2><p>

  96.    The SQL standard allows a <code class="literal">DEFAULT CHARACTER SET</code> clause

  97.    in <code class="command">CREATE SCHEMA</code>, as well as more subcommand

  98.    types than are presently accepted by

  99.    <span class="productname">PostgreSQL</span>.

  100.   </p><p>

  101.    The SQL standard specifies that the subcommands in <code class="command">CREATE

  102.    SCHEMA</code> can appear in any order.  The present

  103.    <span class="productname">PostgreSQL</span> implementation does not

  104.    handle all cases of forward references in subcommands; it might

  105.    sometimes be necessary to reorder the subcommands in order to avoid

  106.    forward references.

  107.   </p><p>

  108.    According to the SQL standard, the owner of a schema always owns

  109.    all objects within it.  <span class="productname">PostgreSQL</span>

  110.    allows schemas to contain objects owned by users other than the

  111.    schema owner.  This can happen only if the schema owner grants the

  112.    <code class="literal">CREATE</code> privilege on their schema to someone else, or a

  113.    superuser chooses to create objects in it.

  114.   </p><p>

  115.    The <code class="literal">IF NOT EXISTS</code> option is a

  116.    <span class="productname">PostgreSQL</span> extension.

  117.   </p></div><div class="refsect1" id="id-1.9.3.80.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-alterschema.html" title="ALTER SCHEMA"><span class="refentrytitle">ALTER SCHEMA</span></a>, <a class="xref" href="sql-dropschema.html" title="DROP SCHEMA"><span class="refentrytitle">DROP SCHEMA</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-createrule.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-createsequence.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">CREATE RULE </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> CREATE SEQUENCE</td></tr></table></div></body></html>
上海开阖软件有限公司 沪ICP备12045867号-1