Do it now
- TODO chrome://gpu
- TODO Presto aggregate function
count(expression)
:计算表达式的非空值的数量。如果你不提供任何表达式,它将计算所有行的数量。sum(expression)
:计算表达式的总和。avg(expression)
:计算表达式的平均值。min(expression)
:计算表达式的最小值。max(expression)
:计算表达式的最大值。approx_percentile(expression, percentile)
:计算表达式的近似百分位数。你需要指定百分位数(介于 0 和 1 之间)。variance(expression)
:计算表达式的方差。stddev(expression)
:计算表达式的标准差。histogram(expression)
:创建一个直方图,显示表达式的值的分布。array_agg(expression)
:将表达式的值合并到一个数组中。map_agg(key_expression, value_expression)
:创建一个映射,其中每个键都是 key_expression 的唯一值,每个值都是 value_expression 的最后一个非空值。checksum(expression)
:计算表达式的校验和。
Usages
Presto aggregate function
SELECT
COUNT(t1.latency) AS count0,
MIN(t1.latency) AS min0,
AVG(t1.latency) AS avg0,
APPROX_PERCENTILE(t1.latency, 0.5) AS median0,
APPROX_PERCENTILE(t1.latency, 0.75) AS p75,
APPROX_PERCENTILE(t1.latency, 0.90) AS p90,
APPROX_PERCENTILE(t1.latency, 0.99) AS p99,
APPROX_PERCENTILE(t1.latency, 0.999) AS p999,
MAX(t1.latency) AS max0,
VARIANCE(t1.latency) AS var0,
STDDEV(t1.latency) AS std0,
HISTOGRAM(t1.latency) AS h0
FROM dev_shopeepay_qa.shark_tracing_span_log__sg_continuous_s0_test t1
WHERE t1.dt = '2023-06-11' AND t1.component = 'grpc'