columns or
expressions in the partition key. If no existing partition matches
the values in the new row, an error will be reported.
</para>
<para>
Partitioned tables do not support <literal>EXCLUDE</literal> constraints;
however, you can define these constraints on individual partitions.
</para>
<para>
See <xref linkend="ddl-partitioning"/> for more discussion on table
partitioning.
</para>
</listitem>
</varlistentry>
<varlistentry id="sql-createtable-partition">
<term><literal>PARTITION OF <replaceable class="parameter">parent_table</replaceable> { FOR VALUES <replaceable class="parameter">partition_bound_spec</replaceable> | DEFAULT }</literal></term>
<listitem>
<para>
Creates the table as a <firstterm>partition</firstterm> of the specified
parent table. The table can be created either as a partition for specific
values using <literal>FOR VALUES</literal> or as a default partition
using <literal>DEFAULT</literal>. Any indexes, constraints and
user-defined row-level triggers that exist in the parent table are cloned
on the new partition.
</para>
<para>
The <replaceable class="parameter">partition_bound_spec</replaceable>
must correspond to the partitioning method and partition key of the
parent table, and must not overlap with any existing partition of that
parent. The form with <literal>IN</literal> is used for list partitioning,
the form with <literal>FROM</literal> and <literal>TO</literal> is used
for range partitioning, and the form with <literal>WITH</literal> is used
for hash partitioning.
</para>
<para>
<replaceable class="parameter">partition_bound_expr</replaceable> is
any variable-free expression (subqueries, window functions, aggregate
functions, and set-returning functions are not allowed). Its data type
must match the data type of the corresponding partition key column.
The expression is evaluated once at table creation time, so it can
even contain volatile expressions such as
<literal><function>CURRENT_TIMESTAMP</function></literal>.
</para>
<para>
When creating a list partition, <literal>NULL</literal> can be
specified to signify that the partition allows the partition key
column to be null. However, there cannot be more than one such
list partition for a given parent table. <literal>NULL</literal>
cannot be specified for range partitions.
</para>
<para>
When creating a range partition, the lower bound specified with
<literal>FROM</literal> is an inclusive bound, whereas the upper
bound specified with <literal>TO</literal> is an exclusive bound.
That is, the values specified in the <literal>FROM</literal> list
are valid values of the corresponding partition key columns for this
partition, whereas those in the <literal>TO</literal> list are
not. Note that this statement must be understood according to the
rules of row-wise comparison (<xref linkend="row-wise-comparison"/>).
For example, given <literal>PARTITION BY RANGE (x,y)</literal>, a partition
bound <literal>FROM (1, 2) TO (3, 4)</literal>
allows <literal>x=1</literal> with any <literal>y>=2</literal>,
<literal>x=2</literal> with any non-null <literal>y</literal>,
and <literal>x=3</literal> with any <literal>y<4</literal>.
</para>
<para>
The special values <literal>MINVALUE</literal> and <literal>MAXVALUE</literal>
may be used when creating a range partition to indicate that there
is no lower or upper bound on the column's value. For example, a
partition defined using <literal>FROM (MINVALUE) TO (10)</literal> allows
any values less than 10, and a partition defined using
<literal>FROM (10) TO (MAXVALUE)</literal> allows any values greater than