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Use the FTS Dictionary dialog to create a full text search dictionary. You
can use a predefined templates or create a new dictionary with custom
The FTS Dictionary dialog organizes the development of a FTS dictionary
through the following dialog tabs: General, Definition, and Options. The
SQL tab displays the SQL code generated by dialog selections.
Use the fields in the General tab to identify the dictionary:
Use the Name field to add a descriptive name for the dictionary. The name
will be displayed in the pgAdmin tree control.
Use the drop-down listbox next to Owner to select the role that will own the
Select the name of the schema in which the dictionary will reside from the
drop-down listbox in the Schema field.
Store notes about the dictionary in the Comment field.
Click the Definition tab to continue.
Use the field in the Definition tab to choose a template from the drop-down
Select ispell to select the Ispell template. The Ispell dictionary template
supports morphological dictionaries, which can normalize many different
linguistic forms of a word into the same lexeme. For example, an English
Ispell dictionary can match all declensions and conjugations of the search
term bank, e.g., banking, banked, banks, banks’, and bank’s. Ispell
dictionaries usually recognize a limited set of words, so they should be
followed by another broader dictionary; for example, a Snowball dictionary,
which recognizes everything.
Select simple to select the simple template. The simple dictionary template
operates by converting the input token to lower case and checking it against
a file of stop words. If it is found in the file then an empty array is
returned, causing the token to be discarded. If not, the lower-cased form of
the word is returned as the normalized lexeme. Alternatively, the dictionary
can be configured to report non-stop-words as unrecognized, allowing them to
be passed on to the next dictionary in the list.
Select snowball to select the Snowball template. The Snowball dictionary
template is based on a project by Martin Porter, inventor of the popular
Porter’s stemming algorithm for the English language. Snowball now provides
stemming algorithms for many languages (see the Snowball site for more
information). Each algorithm understands how to reduce common variant forms of
words to a base, or stem, spelling within its language. A Snowball dictionary
recognizes everything, whether or not it is able to simplify the word, so it
should be placed at the end of the dictionary list. It is useless to have it
before any other dictionary because a token will never pass through it to the
Select synonym to select the synonym template. This dictionary template is
used to create dictionaries that replace a word with a synonym. Phrases are not
supported (use the thesaurus template (Section 12.6.4) for that). A synonym
dictionary can be used to overcome linguistic problems, for example, to prevent
an English stemmer dictionary from reducing the word Paris to pari.
Select thesaurus to select the thesaurus template. A thesaurus dictionary
replaces all non-preferred terms by one preferred term and, optionally,
preserves the original terms for indexing as well. PostgreSQL’s current
implementation of the thesaurus dictionary is an extension of the synonym
dictionary with added phrase support.
Click the Options tab to continue.
Use the fields in the Options tab to provide template-specific options. Click
the Add icon (+) to add an option clause:
Specify the name of an option in the Option field
Provide a value for the option in the Value field.
Click the Add icon (+) to specify each additional option/value pair; to
discard an option, click the trash icon to the left of the row and confirm
deletion in the Delete Row popup.
Click the SQL tab to continue.
Your entries in the FTS Dictionary dialog generate a generate a SQL command.
Use the SQL tab for review; revisit or switch tabs to make any changes to the
The following is an example of the sql command generated by user selections in
the FTS Dictionary dialog:
The example shown demonstrates creating a custom dictionary named
more_stopwords which is based on the simple template and is configured to use standard English.
Click the Info button (i) to access online help.
Click the Save button to save work.
Click the Cancel button to exit without saving work.
Click the Reset button to restore configuration parameters.