我在sqlite中有一个名为param_vals_breaches的表,如下所示：
id param queue date_time param_val breach_count 1 c a 2013-01-01 00:00:00 188 7 2 c b 2013-01-01 00:00:00 156 8 3 c c 2013-01-01 00:00:00 100 2 4 d a 2013-01-01 00:00:00 657 0 5 d b 2013-01-01 00:00:00 23 6 6 d c 2013-01-01 00:00:00 230 12 7 c a 2013-01-01 01:00:00 100 0 8 c b 2013-01-01 01:00:00 143 9 9 c c 2013-01-01 01:00:00 12 2 10 d a 2013-01-01 01:00:00 0 1 11 d b 2013-01-01 01:00:00 29 5 12 d c 2013-01-01 01:00:00 22 14 13 c a 2013-01-01 02:00:00 188 7 14 c b 2013-01-01 02:00:00 156 8 15 c c 2013-01-01 02:00:00 100 2 16 d a 2013-01-01 02:00:00 657 0 17 d b 2013-01-01 02:00:00 23 6 18 d c 2013-01-01 02:00:00 230 12
我想写一个查询,它将显示一个特定的队列(例如“a”),每个小时的基础上每个参数的平均值为param_val和breach_count.因此,转换数据以获得如下所示的内容：
Results for Queue A
Hour 0 Hour 0 Hour 1 Hour 1 Hour 2 Hour 2
param avg_param_val avg_breach_count avg_param_val avg_breach_count avg_param_val avg_breach_count
c xxx xxx xxx xxx xxx xxx
d xxx xxx xxx xxx xxx xxx
这可能吗？我不知道该怎么做.谢谢！
sqlite没有PIVOT函数,但您可以使用带有CASE表达式的聚合函数将行转换为列：
原文链接：https://www.f2er.com/sqlite/197876.htmlselect param,avg(case when time = '00' then param_val end) AvgHour0Val,avg(case when time = '00' then breach_count end) AvgHour0Count,avg(case when time = '01' then param_val end) AvgHour1Val,avg(case when time = '01' then breach_count end) AvgHour1Count,avg(case when time = '02' then param_val end) AvgHour2Val,avg(case when time = '02' then breach_count end) AvgHour2Count
from
(
select param,strftime('%H',date_time) time,param_val,breach_count
from param_vals_breaches
where queue = 'a'
) src
group by param;
