FIRST Function Example | Teradata Vantage - 17.00 - Example: Using FIRST to Return the Temperature - Teradata Database

Teradata Vantageā„¢ - Time Series Tables and Operations

prodname
Advanced SQL Engine
Teradata Database
vrm_release
17.00
created_date
June 2020
category
Programming Reference
featnum
B035-1208-170K
/*PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, FIRST(TEMPERATURE)
FROM OCEAN_BUOYS
WHERE TD_TIMECODE BETWEEN TIMESTAMP '2014-01-06 08:00:00' AND TIMESTAMP '2014-01-06 10:30:00'
GROUP BY TIME (MINUTES(10) AND BUOYID)
ORDER BY 2,3,4;

/*Non-PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, FIRST(TEMPERATURE)
FROM OCEAN_BUOYS_NONPTI
WHERE TIMECODE BETWEEN TIMESTAMP '2014-01-06 08:00:00' AND TIMESTAMP '2014-01-06 10:30:00'
GROUP BY TIME (MINUTES(10) AND BUOYID)
USING TIMECODE(TIMECODE)
ORDER BY 2,3,4;

The result set is the same for both examples. The ties are returned in Rows 3 and 4, below.

TIMECODE_ RANGE GROUP BY TIME (MINUTES(10)) BUOYID First (TEMPERATURE)
('2014-01-06 10:00:00.000000+00:00', '2014-01-06 10:10:00.000000+00:00') 13 44 43
('2014-01-06 09:00:00.000000+00:00', '2014-01-06 09:10:00.000000+00:00') 7 1 70
('2014-01-06 09:00:00.000000+00:00', '2014-01-06 09:10:00.000000+00:00') 7 1 77
('2014-01-06 08:10:00.000000+00:00', '2014-01-06 08:20:00.000000+00:00') 2 0 10
('2014-01-06 08:00:00.000000+00:00', '2014-01-06 08:10:00.000000+00:00') 1 0 10