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>12.12. Migration from Pre-8.3 Text Search</A
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> Applications that use the <A
HREF="tsearch2.html"
>tsearch2</A
>
module for text searching will need some adjustments to work
with the
built-in features:
</P
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><LI
><P
> Some functions have been renamed or had small adjustments in their
argument lists, and all of them are now in the <TT
CLASS="LITERAL"
>pg_catalog</TT
>
schema, whereas in a previous installation they would have been in
<TT
CLASS="LITERAL"
>public</TT
> or another non-system schema. There is a new
version of <SPAN
CLASS="APPLICATION"
>tsearch2</SPAN
>
that provides a compatibility layer to solve most problems in this
area.
</P
></LI
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> The old <SPAN
CLASS="APPLICATION"
>tsearch2</SPAN
> functions and other objects
<SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>must</I
></SPAN
> be suppressed when loading <SPAN
CLASS="APPLICATION"
>pg_dump</SPAN
>
output from a pre-8.3 database. While many of them won't load anyway,
a few will and then cause problems. One simple way to deal with this
is to load the new <SPAN
CLASS="APPLICATION"
>tsearch2</SPAN
> module before restoring
the dump; then it will block the old objects from being loaded.
</P
></LI
><LI
><P
> Text search configuration setup is completely different now.
Instead of manually inserting rows into configuration tables,
search is configured through the specialized SQL commands shown
earlier in this chapter. There is no automated
support for converting an existing custom configuration for 8.3;
you're on your own here.
</P
></LI
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><P
> Most types of dictionaries rely on some outside-the-database
configuration files. These are largely compatible with pre-8.3
usage, but note the following differences:
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> Configuration files now must be placed in a single specified
directory (<TT
CLASS="FILENAME"
>$SHAREDIR/tsearch_data</TT
>), and must have
a specific extension depending on the type of file, as noted
previously in the descriptions of the various dictionary types.
This restriction was added to forestall security problems.
</P
></LI
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> Configuration files must be encoded in UTF-8 encoding,
regardless of what database encoding is used.
</P
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><P
> In thesaurus configuration files, stop words must be marked with
<TT
CLASS="LITERAL"
>?</TT
>.
</P
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