例: GROUP BY TIMEとUNION - Teradata Database - Teradata Vantage NewSQL Engine

次の例は、タイムコードがクエリーごとであると推測したルールを示していますが、今回は、UNIONを使用した場合のルールを示しています。

select Q.avrg, Q.md, Q.grp
from
(
 sel avg(temperature) as avrg, mode(temperature) as md, 1 as grp
 from OCEAN_BUOYS
 group by time(minutes(5) and buoyid)

 union

 sel avg(temperature) as avrg, mode(temperature) as md, 0 as grp
 from OCEAN_BUOYS
 group by time(minutes(10) and buoyid)
) as Q
order by 1;

select Q.avrg, Q.md, Q.grp
from
(
 sel avg(temperature) as avrg, mode(temperature) as md, 1 as grp
 from ocean_buoys
 group by time(minutes(5) and buoyid)

 union

 sel avg(temperature) as avrg, mode(temperature) as md, 0 as grp
 from ocean_buoys_nonpti
 group by time(minutes(10) and buoyid)
) as Q

order by 1;

*** Failure 4359 Time Series: GROUP BY TIME clause may not be used without an implicit or explicit TIMECODE specification