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>14.6. Creating the Operator Class</A
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> Now that we have the required operators and support routine,
we can finally create the operator class:
</P><PRE
CLASS="PROGRAMLISTING"
>CREATE OPERATOR CLASS complex_abs_ops
DEFAULT FOR TYPE complex USING btree AS
OPERATOR 1 < ,
OPERATOR 2 <= ,
OPERATOR 3 = ,
OPERATOR 4 >= ,
OPERATOR 5 > ,
FUNCTION 1 complex_abs_cmp(complex, complex);</PRE
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> And we're done! (Whew.) It should now be possible to create
and use B-tree indexes on <TT
CLASS="TYPE"
>complex</TT
> columns.
</P
><P
> We could have written the operator entries more verbosely, as in
</P><PRE
CLASS="PROGRAMLISTING"
> OPERATOR 1 < (complex, complex) ,</PRE
><P>
but there is no need to do so when the operators take the same data type
we are defining the operator class for.
</P
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> The above example assumes that you want to make this new operator class the
default B-tree operator class for the <TT
CLASS="TYPE"
>complex</TT
> data type.
If you don't, just leave out the word <TT
CLASS="LITERAL"
>DEFAULT</TT
>.
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