(PECL sphinx >= 0.1.0)
SphinxClient::setGroupBy — Set grouping attribute
$attribute
, int $func
[, string $groupsort = "@group desc"
] )Sets grouping attribute, function, and group sorting mode, and enables grouping.
Grouping feature is very similar to GROUP BY clause in SQL. Results produced by this function call are going to be the same as produced by the following pseudo code: SELECT ... GROUP BY $func($attribute) ORDER BY $groupsort.
attribute
A string containing group-by attribute name.
func
Constant, which sets a function applied to the attribute value in order to compute group-by key.
groupsort
An optional clause controlling how the groups are sorted.
成功时返回 TRUE， 或者在失败时返回 FALSE。