<literal>toast.log_autovacuum_min_duration</literal> (<type>integer</type>)
    <indexterm>
     <primary><varname>log_autovacuum_min_duration</varname></primary>
     <secondary>storage parameter</secondary>
    </indexterm>
    </term>
    <listitem>
     <para>
      Per-table value for <xref linkend="guc-log-autovacuum-min-duration"/>
      parameter.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry id="reloption-vacuum-max-eager-freeze-failure-rate" xreflabel="vacuum_max_eager_freeze_failure_rate">
    <term><literal>vacuum_max_eager_freeze_failure_rate</literal>, <literal>toast.vacuum_max_eager_freeze_failure_rate</literal> (<type>floating point</type>)
    <indexterm>
     <primary><varname>vacuum_max_eager_freeze_failure_rate</varname></primary>
     <secondary>storage parameter</secondary>
    </indexterm>
    </term>
    <listitem>
     <para>
      Per-table value for <xref linkend="guc-vacuum-max-eager-freeze-failure-rate"/>
      parameter.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry id="reloption-user-catalog-table" xreflabel="user_catalog_table">
    <term><literal>user_catalog_table</literal> (<type>boolean</type>)
    <indexterm>
     <primary><varname>user_catalog_table</varname> storage parameter</primary>
    </indexterm>
    </term>
    <listitem>
     <para>
      Declare the table as an additional catalog table for purposes of
      logical replication. See
      <xref linkend="logicaldecoding-capabilities"/> for details.
      This parameter cannot be set for TOAST tables.
     </para>
    </listitem>
   </varlistentry>

   </variablelist>

  </refsect2>
 </refsect1>

 <refsect1 id="sql-createtable-notes">
  <title>Notes</title>
    <para>
     <productname>PostgreSQL</productname> automatically creates an
     index for each unique constraint and primary key constraint to
     enforce uniqueness.  Thus, it is not necessary to create an
     index explicitly for primary key columns.  (See <xref
     linkend="sql-createindex"/> for more information.)
    </para>

    <para>
     Unique constraints and primary keys are not inherited in the
     current implementation.  This makes the combination of
     inheritance and unique constraints rather dysfunctional.
    </para>

    <para>
     A table cannot have more than 1600 columns.  (In practice, the
     effective limit is usually lower because of tuple-length constraints.)
    </para>

 </refsect1>


 <refsect1 id="sql-createtable-examples">
  <title>Examples</title>

  <para>
   Create table <structname>films</structname> and table
   <structname>distributors</structname>:

<programlisting>
CREATE TABLE films (
    code        char(5) CONSTRAINT firstkey PRIMARY KEY,
    title       varchar(40) NOT NULL,
    did         integer NOT NULL,
    date_prod   date,
    kind        varchar(10),
    len         interval hour to minute
);

CREATE TABLE distributors (
     did    integer PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,
     name   varchar(40) NOT NULL CHECK (name &lt;&gt; '')
);
</programlisting>
  </para>

  <para>
   Create a table with a 2-dimensional array:

<programlisting>
CREATE TABLE array_int (
    vector  int[][]
);
</programlisting>
  </para>

  <para>
   Define a unique table constraint for the table
   <literal>films</literal>.  Unique table constraints can be defined
   on one or more columns of the table:

<programlisting>
CREATE TABLE films (
    code        char(5),
    title       varchar(40),
    did         integer,
    date_prod   date,
    kind        varchar(10),
    len         interval hour to minute,
    CONSTRAINT production UNIQUE(date_prod)
);
</programlisting>
  </para>

  <para>
   Define a check column constraint:

<programlisting>
CREATE TABLE distributors (
    did     integer CHECK (did &gt; 100),
    name    varchar(40)
);
</programlisting>
  </para>

  <para>
   Define a check table constraint:

<programlisting>
CREATE TABLE distributors (
    did     integer,
    name    varchar(40),