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61th chunk of `doc/src/sgml/func.sgml`
e45e4a24b9583152fab5119fb99a51d809c0e84481e697270000000100000faa
     <lineannotation>\x04d2</lineannotation>
cast(1234 as bytea)            <lineannotation>\x000004d2</lineannotation>
cast(-1234 as bytea)           <lineannotation>\xfffffb2e</lineannotation>
'\x8000'::bytea::smallint      <lineannotation>-32768</lineannotation>
'\x8000'::bytea::integer       <lineannotation>32768</lineannotation>
</programlisting>
   Casting a <type>bytea</type> to an integer will raise an error if the
   length of the <type>bytea</type> exceeds the width of the integer type.
  </para>

  <para>
   See also the aggregate function <function>string_agg</function> in
   <xref linkend="functions-aggregate"/> and the large object functions
   in <xref linkend="lo-funcs"/>.
  </para>
 </sect1>


  <sect1 id="functions-bitstring">
   <title>Bit String Functions and Operators</title>

   <indexterm zone="functions-bitstring">
    <primary>bit strings</primary>
    <secondary>functions</secondary>
   </indexterm>

   <para>
    This section describes functions and operators for examining and
    manipulating bit strings, that is values of the types
    <type>bit</type> and <type>bit varying</type>.  (While only
    type <type>bit</type> is mentioned in these tables, values of
    type <type>bit varying</type> can be used interchangeably.)
    Bit strings support the usual comparison operators shown in
    <xref linkend="functions-comparison-op-table"/>, as well as the
    operators shown in <xref linkend="functions-bit-string-op-table"/>.
   </para>

   <table id="functions-bit-string-op-table">
    <title>Bit String Operators</title>
    <tgroup cols="1">
     <thead>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        Operator
       </para>
       <para>
        Description
       </para>
       <para>
        Example(s)
       </para></entry>
      </row>
     </thead>

     <tbody>
      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <type>bit</type> <literal>||</literal> <type>bit</type>
        <returnvalue>bit</returnvalue>
       </para>
       <para>
        Concatenation
       </para>
       <para>
        <literal>B'10001' || B'011'</literal>
        <returnvalue>10001011</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <type>bit</type> <literal>&amp;</literal> <type>bit</type>
        <returnvalue>bit</returnvalue>
       </para>
       <para>
        Bitwise AND (inputs must be of equal length)
       </para>
       <para>
        <literal>B'10001' &amp; B'01101'</literal>
        <returnvalue>00001</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <type>bit</type> <literal>|</literal> <type>bit</type>
        <returnvalue>bit</returnvalue>
       </para>
       <para>
        Bitwise OR (inputs must be of equal length)
       </para>
       <para>
        <literal>B'10001' | B'01101'</literal>
        <returnvalue>11101</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <type>bit</type> <literal>#</literal> <type>bit</type>
        <returnvalue>bit</returnvalue>
       </para>
       <para>
        Bitwise exclusive OR (inputs must be of equal length)
       </para>
       <para>
        <literal>B'10001' # B'01101'</literal>
        <returnvalue>11100</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <literal>~</literal> <type>bit</type>
        <returnvalue>bit</returnvalue>
       </para>
       <para>
        Bitwise NOT
       </para>
       <para>
        <literal>~ B'10001'</literal>
        <returnvalue>01110</returnvalue>
       </para></entry>
      </row>

      <row>
       <entry role="func_table_entry"><para role="func_signature">
        <type>bit</type> <literal>&lt;&lt;</literal>
Title: Bytea Casting Examples, String Aggregation, and Bit String Functions
Summary
This section provides examples of casting between integers and the bytea data type, illustrating how integers are represented as byte sequences. It also mentions the potential for errors when casting bytea to integers if the bytea length exceeds the integer type's width. The section then transitions to bit string functions and operators, outlining operations like concatenation, bitwise AND, OR, XOR, NOT, left shift, and right shift. It describes the behavior of these operators on bit strings, including the requirement for equal length inputs in some cases.