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>Appendix F. Additional Supplied Modules</TD
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><A
NAME="DICT-INT"
>F.10. dict_int</A
></H1
><P
> <TT
CLASS="FILENAME"
>dict_int</TT
> is an example of an add-on dictionary template
for full-text search. The motivation for this example dictionary is to
control the indexing of integers (signed and unsigned), allowing such
numbers to be indexed while preventing excessive growth in the number of
unique words, which greatly affects the performance of searching.
</P
><DIV
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><H2
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><A
NAME="AEN147951"
>F.10.1. Configuration</A
></H2
><P
> The dictionary accepts two options:
</P
><P
></P
><UL
><LI
><P
> The <TT
CLASS="LITERAL"
>maxlen</TT
> parameter specifies the maximum number of
digits allowed in an integer word. The default value is 6.
</P
></LI
><LI
><P
> The <TT
CLASS="LITERAL"
>rejectlong</TT
> parameter specifies whether an overlength
integer should be truncated or ignored. If <TT
CLASS="LITERAL"
>rejectlong</TT
> is
<TT
CLASS="LITERAL"
>false</TT
> (the default), the dictionary returns the first
<TT
CLASS="LITERAL"
>maxlen</TT
> digits of the integer. If <TT
CLASS="LITERAL"
>rejectlong</TT
> is
<TT
CLASS="LITERAL"
>true</TT
>, the dictionary treats an overlength integer as a stop
word, so that it will not be indexed. Note that this also means that
such an integer cannot be searched for.
</P
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><A
NAME="AEN147966"
>F.10.2. Usage</A
></H2
><P
> Installing the <TT
CLASS="LITERAL"
>dict_int</TT
> extension creates a text search
template <TT
CLASS="LITERAL"
>intdict_template</TT
> and a dictionary <TT
CLASS="LITERAL"
>intdict</TT
>
based on it, with the default parameters. You can alter the
parameters, for example
</P><PRE
CLASS="PROGRAMLISTING"
>mydb# ALTER TEXT SEARCH DICTIONARY intdict (MAXLEN = 4, REJECTLONG = true);
ALTER TEXT SEARCH DICTIONARY</PRE
><P>
or create new dictionaries based on the template.
</P
><P
> To test the dictionary, you can try
</P><PRE
CLASS="PROGRAMLISTING"
>mydb# select ts_lexize('intdict', '12345678');
ts_lexize
-----------
{123456}</PRE
><P>
but real-world usage will involve including it in a text search
configuration as described in <A
HREF="textsearch.html"
>Chapter 12</A
>.
That might look like this:
</P><PRE
CLASS="PROGRAMLISTING"
>ALTER TEXT SEARCH CONFIGURATION english
ALTER MAPPING FOR int, uint WITH intdict;</PRE
><P>
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