The table `taxonomy_term_data` lists the terms. In this table, the term string is found in the `name` field. The field `vid` identifies the vocabulary assocaiated with the term. And the field `tid` is the numeric taxonomy id. So you can look up the relationship between the term `name`, `tid` and `vid` directly from the this table. The to determine the vocabulary name string associated with the term, you need to left join the `taxonomy_vocabulary.name` field, where `taxonomy_vocabulary.vid` = `taxonomy_term_data.vid`.