HLL_EMPTY

description

Syntax

HLL_EMPTY(value)

HLL_EMPTY 返回一个 hll 类型的空值。

example

1. MySQL > select hll_cardinality(hll_empty());
2. +------------------------------+
3. | hll_cardinality(hll_empty()) |
4. +------------------------------+
5. |                            0 |
6. +------------------------------+

keywords

HLL,HLL_EMPTY