Re: Full-text indexing

On Wed, 20 Feb 2002 16:13:06 +0100, "S" <sliver_1_at_poczta.onet.pl> wrote:
>Hello, I am beginner in Oracle and I need some help.
>I have files of text (ASCII) and I need to put pointers to them into the
>table.

...
> Can I remove blobs from the table and keep
>just index? If I empty the table and set new files and then run incremental
>index - will new files be added to index or index will be rebuilded and
>information about removed files will be lost?

You can get the index to reside in the database, even though the files stay as text on the server, by using this line before building the index:

ctx_ddl.create_preference('my_preference_name', 'FILE_DATASTORE');

Then you fill in details about the index through further calls to CTX_DDL, e.g. how to handle punctuation characters.

In the indexed column, you just keep the absolute pathname of each text or HTML file, which must reside on the database server. (Sometimes this is tricky to ensure when the web server and DB server are on different machines.)

Calling ctx_ddl.sync_index('my_index_name') will rebuild just those portions of the index where the pathname value has been updated. So it will automatically pick up any new rows, and to specify which rows represent updated text files, you can just issue an UPDATE to set path_column = path_column (i.e. update it to the original value).

John

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