Snowball Dictionary¶
A Snowball dictionary is based on a project by Martin Porter and is used for stem analysis, providing stemming algorithms for many languages. GaussDB(DWS) provides predefined Snowball dictionaries of many languages. You can query the PG_TS_DICT system catalog to view the predefined Snowball dictionaries and supported stemming algorithms.
Snowball dictionaries identify all inputs as recognized, whether simplified or not, so they should be placed at the end of the dictionary list. It is useless to place it before any other dictionary because a token will never pass it through to the next dictionary.
For details about the syntax of Snowball dictionaries, see CREATE TEXT SEARCH DICTIONARY.