doc/src/sgml/ref/alter_view.sgml

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   2 $PostgreSQL$
   3 PostgreSQL documentation
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   5
   6 <refentry id="SQL-ALTERVIEW">
   7  <refmeta>
   8   <refentrytitle id="SQL-ALTERVIEW-TITLE">ALTER VIEW</refentrytitle>
   9   <refmiscinfo>SQL - Language Statements</refmiscinfo>
  10  </refmeta>
  11
  12  <refnamediv>
  13   <refname>ALTER VIEW</refname>
  14   <refpurpose>change the definition of a view</refpurpose>
  15  </refnamediv>
  16
  17  <indexterm zone="sql-alterview">
  18   <primary>ALTER VIEW</primary>
  19  </indexterm>
  20
  21  <refsynopsisdiv>
  22 <synopsis>
  23 ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET DEFAULT <replaceable class="PARAMETER">expression</replaceable>
  24 ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> DROP DEFAULT
  25 ALTER VIEW <replaceable class="parameter">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
  26 ALTER VIEW <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
  27 ALTER VIEW <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
  28 </synopsis>
  29  </refsynopsisdiv>
  30
  31  <refsect1>
  32   <title>Description</title>
  33
  34   <para>
  35    <command>ALTER VIEW</command> changes various auxiliary properties
  36    of a view.  (If you want to modify the view's defining query,
  37    use <command>CREATE OR REPLACE VIEW</>.)
  38   </para>
  39
  40   <para>
  41    You must own the view to use <command>ALTER VIEW</>.
  42    To change a view's schema, you must also have <literal>CREATE</>
  43    privilege on the new schema.
  44    To alter the owner, you must also be a direct or indirect member of the new
  45    owning role, and that role must have <literal>CREATE</literal> privilege on
  46    the view's schema.  (These restrictions enforce that altering the owner
  47    doesn't do anything you couldn't do by dropping and recreating the view.
  48    However, a superuser can alter ownership of any view anyway.)
  49   </para>
  50  </refsect1>
  51
  52  <refsect1>
  53   <title>Parameters</title>
  54
  55   <variablelist>
  56    <varlistentry>
  57     <term><replaceable class="parameter">name</replaceable></term>
  58     <listitem>
  59      <para>
  60       The name (optionally schema-qualified) of an existing view.
  61      </para>
  62     </listitem>
  63    </varlistentry>
  64
  65    <varlistentry>
  66     <term><literal>SET</literal>/<literal>DROP DEFAULT</literal></term>
  67     <listitem>
  68      <para>
  69       These forms set or remove the default value for a column.
  70       A default value associated with a view column is
  71       inserted into <command>INSERT</> statements on the view before
  72       the view's <literal>ON INSERT</literal> rule is applied, if
  73       the <command>INSERT</> does not specify a value for the column.
  74      </para>
  75     </listitem>
  76    </varlistentry>
  77
  78    <varlistentry>
  79     <term><replaceable class="PARAMETER">new_owner</replaceable></term>
  80     <listitem>
  81      <para>
  82       The user name of the new owner of the view.
  83      </para>
  84     </listitem>
  85    </varlistentry>
  86
  87    <varlistentry>
  88     <term><replaceable class="parameter">new_name</replaceable></term>
  89     <listitem>
  90      <para>
  91       The new name for the view.
  92      </para>
  93     </listitem>
  94    </varlistentry>
  95
  96    <varlistentry>
  97     <term><replaceable class="parameter">new_schema</replaceable></term>
  98     <listitem>
  99      <para>
 100       The new schema for the view.
 101      </para>
 102     </listitem>
 103    </varlistentry>
 104   </variablelist>
 105  </refsect1>
 106
 107  <refsect1>
 108   <title>Notes</title>
 109
 110   <para>
 111    For historical reasons, <command>ALTER TABLE</command> can be used with
 112    views too; but the only variants of <command>ALTER TABLE</command>
 113    that are allowed with views are equivalent to the ones shown above.
 114   </para>
 115  </refsect1>
 116
 117  <refsect1>
 118   <title>Examples</title>
 119
 120   <para>
 121    To rename the view <literal>foo</literal> to
 122    <literal>bar</literal>:
 123 <programlisting>
 124 ALTER VIEW foo RENAME TO bar;
 125 </programlisting>
 126   </para>
 127  </refsect1>
 128
 129  <refsect1>
 130   <title>Compatibility</title>
 131
 132   <para>
 133    <command>ALTER VIEW</command> is a <productname>PostgreSQL</>
 134    extension of the SQL standard.
 135   </para>
 136  </refsect1>
 137
 138  <refsect1>
 139   <title>See Also</title>
 140
 141   <simplelist type="inline">
 142    <member><xref linkend="sql-createview" endterm="sql-createview-title"></member>
 143    <member><xref linkend="sql-dropview" endterm="sql-dropview-title"></member>
 144   </simplelist>
 145  </refsect1>
 146 </refentry>