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18th chunk of `doc/src/sgml/brin.sgml`
cb3e8fff86e0f4da7b631b31fb755c216594f086596e7db6000000010000082e
 <entry>Support Procedure 5</entry>
     <entry>internal function <function>brin_bloom_options()</function></entry>
    </row>
    <row>
     <entry>Support Procedure 11</entry>
     <entry>function to compute hash of an element</entry>
    </row>
    <row>
     <entry>Operator Strategy 1</entry>
     <entry>operator equal-to</entry>
    </row>
   </tbody>
  </tgroup>
 </table>

 <para>
    Support procedure numbers 1-10 are reserved for the BRIN internal
    functions, so the SQL level functions start with number 11.  Support
    function number 11 is the main function required to build the index.
    It should accept one argument with the same data type as the operator class,
    and return a hash of the value.
 </para>

 <para>
  The minmax-multi operator class is also intended for data types implementing
  a totally ordered set, and may be seen as a simple extension of the minmax
  operator class. While minmax operator class summarizes values from each block
  range into a single contiguous interval, minmax-multi allows summarization
  into multiple smaller intervals to improve handling of outlier values.
  It is possible to use the minmax-multi support procedures alongside the
  corresponding operators, as shown in
  <xref linkend="brin-extensibility-minmax-multi-table"/>.
  All operator class members (procedures and operators) are mandatory.
 </para>

 <table id="brin-extensibility-minmax-multi-table">
  <title>Procedure and Support Numbers for minmax-multi Operator Classes</title>
  <tgroup cols="2">
   <thead>
    <row>
     <entry>Operator class member</entry>
     <entry>Object</entry>
    </row>
   </thead>
   <tbody>
    <row>
     <entry>Support Procedure 1</entry>
     <entry>internal function <function>brin_minmax_multi_opcinfo()</function></entry>
    </row>
    <row>
     <entry>Support Procedure 2</entry>
     <entry>internal function <function>brin_minmax_multi_add_value()</function></entry>
    </row>
    <row>
     <entry>Support Procedure 3</entry>
     <entry>internal function <function>brin_minmax_multi_consistent()</function></entry>
Title: Minmax-Multi Operator Class Support Procedures
Summary
The minmax-multi operator class is an extension of the minmax class, allowing for summarization of values into multiple intervals to handle outlier values. It requires mandatory operator class members, including support procedures such as brin_minmax_multi_opcinfo and brin_minmax_multi_consistent. The class is intended for data types that implement a totally ordered set and can be used to improve indexing and querying efficiency.