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29th chunk of `doc/src/sgml/spi.sgml`
690dde814566aa6e2d89e870004f3b46be8fcc55f4bf545a0000000100000fa3
 for example it might not
   return tuples.  If you simply pass the <type>Portal</type> pointer
   to other SPI functions, they can defend themselves against such
   cases, but caution is appropriate when directly inspecting
   the <type>Portal</type>.
  </para>
 </refsect1>
</refentry>

<!-- *********************************************** -->

<refentry id="spi-spi-cursor-fetch">
 <indexterm><primary>SPI_cursor_fetch</primary></indexterm>

 <refmeta>
  <refentrytitle>SPI_cursor_fetch</refentrytitle>
  <manvolnum>3</manvolnum>
 </refmeta>

 <refnamediv>
  <refname>SPI_cursor_fetch</refname>
  <refpurpose>fetch some rows from a cursor</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
void SPI_cursor_fetch(Portal <parameter>portal</parameter>, bool <parameter>forward</parameter>, long <parameter>count</parameter>)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <function>SPI_cursor_fetch</function> fetches some rows from a
   cursor.  This is equivalent to a subset of the SQL command
   <command>FETCH</command> (see <function>SPI_scroll_cursor_fetch</function>
   for more functionality).
  </para>
 </refsect1>

 <refsect1>
  <title>Arguments</title>

  <variablelist>
   <varlistentry>
    <term><literal>Portal <parameter>portal</parameter></literal></term>
    <listitem>
     <para>
      portal containing the cursor
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>bool <parameter>forward</parameter></literal></term>
    <listitem>
     <para>
      true for fetch forward, false for fetch backward
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>long <parameter>count</parameter></literal></term>
    <listitem>
     <para>
      maximum number of rows to fetch
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Return Value</title>

  <para>
   <varname>SPI_processed</varname> and
   <varname>SPI_tuptable</varname> are set as in
   <function>SPI_execute</function> if successful.
  </para>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   Fetching backward may fail if the cursor's plan was not created
   with the <symbol>CURSOR_OPT_SCROLL</symbol> option.
  </para>
 </refsect1>
</refentry>

<!-- *********************************************** -->

<refentry id="spi-spi-cursor-move">
 <indexterm><primary>SPI_cursor_move</primary></indexterm>

 <refmeta>
  <refentrytitle>SPI_cursor_move</refentrytitle>
  <manvolnum>3</manvolnum>
 </refmeta>

 <refnamediv>
  <refname>SPI_cursor_move</refname>
  <refpurpose>move a cursor</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
void SPI_cursor_move(Portal <parameter>portal</parameter>, bool <parameter>forward</parameter>, long <parameter>count</parameter>)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <function>SPI_cursor_move</function> skips over some number of rows
   in a cursor.  This is equivalent to a subset of the SQL command
   <command>MOVE</command> (see <function>SPI_scroll_cursor_move</function>
   for more functionality).
  </para>
 </refsect1>

 <refsect1>
  <title>Arguments</title>

  <variablelist>
   <varlistentry>
    <term><literal>Portal <parameter>portal</parameter></literal></term>
    <listitem>
     <para>
      portal containing the cursor
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>bool <parameter>forward</parameter></literal></term>
    <listitem>
     <para>
      true for move forward, false for move backward
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>long <parameter>count</parameter></literal></term>
    <listitem>
     <para>
      maximum number of rows to move
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   Moving backward may fail if the cursor's plan was not created
   with
Title: SPI_cursor_fetch and SPI_cursor_move: Functions to Manipulate Cursors
Summary
This section describes the functions `SPI_cursor_fetch` and `SPI_cursor_move`, used to fetch rows from and move within a cursor, respectively. `SPI_cursor_fetch` fetches a specified number of rows from a cursor in either forward or backward direction, setting `SPI_processed` and `SPI_tuptable` upon success. `SPI_cursor_move` skips a specified number of rows in a cursor, also in either forward or backward direction. Both functions require a portal containing the cursor and support moving or fetching in either direction, subject to the cursor's scrollability.