(PECL sphinx >= 0.1.0)
SphinxClient::setGroupDistinct — Set attribute name for per-group distinct values count calculations
Sets attribute name for per-group distinct values count calculations. Only available for grouping queries. For each group, all values of attribute will be stored, then the amount of distinct values will be calculated and returned to the client. This feature is similar to COUNT(DISTINCT) clause in SQL.
A string containing group-by attribute name.
成功した場合に TRUE を、失敗した場合に FALSE を返します。