dcount_hll()dcount_hll()
根据 hll 结果(已由 hll 或 hll_merge 生成)计算 dcount。Calculates the dcount from hll results (that were generated by hll or hll_merge).
阅读基础算法 (HyperLogLog ) 和估算准确度。Read about the underlying algorithm ( H yper L og L og) and estimation accuracy.
语法Syntax
dcount_hll(
Expr)
dcount_hll(
Expr)
参数Arguments
返回Returns
Expr 中每个值的非重复计数The distinct count of each value in Expr
示例Examples
StormEvents
| summarize hllRes = hll(DamageProperty) by bin(StartTime,10m)
| summarize hllMerged = hll_merge(hllRes)
| project dcount_hll(hllMerged)
dcount_hll_hllMergeddcount_hll_hllMerged |
---|
315315 |