hll_raw_agg
This function is an aggregate function that is used to aggregate HLL fields. It returns an HLL value.
Syntaxβ
hll_raw_agg(hll)
Parametersβ
hll
: the HLL column that is generated by other columns or based on the loaded data.
Return valueβ
Returns a value of the HLL type.
Examplesβ
mysql> select k1, hll_cardinality(hll_raw_agg(v1)) from tbl group by k1;
+------+----------------------------------+
| k1 | hll_cardinality(hll_raw_agg(`v1`)) |
+------+----------------------------------+
| 2 | 4 |
| 1 | 3 |
+------+----------------------------------+