HLL_EMPTY

description

Syntax

HLL_EMPTY(value)

HLL_EMPTY 返回一个 hll 类型的空值。

example

MySQL > select hll_cardinality(hll_empty());
+------------------------------+
| hll_cardinality(hll_empty()) |
+------------------------------+
|                            0 |
+------------------------------+

keywords

HLL,HLL_EMPTY