MAXIMUM Function Examples | Teradata Vantage - 17.00 - Examples: Using MAXIMUM with Time Series - 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

Example: Calculating the Maximum for PTI and non-PTI Tables

The following example shows how the MAX function can be used with both Primary Time Index (PTI) and non-PTI tables.

The examples use the tables and data setup in Table and Data Definition for Time Series Aggregates Examples.

/*PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, MAX(TEMPERATURE), COUNT(*)
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 3,2,1;

/*Non-PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, MAX(TEMPERATURE), COUNT(*)
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 3,2,1;

Result:

The results of both queries are identical so only one result set is shown.
TIMECODE_RANGE GROUP BY TIME (MINUTES(10)) BUOYID MAX (TEMPERATURE) COUNT(*)
('2014-01-06 08:00:00.000000+00:00', '2014-01-06 08:10:00.000000+00:00') 1 0 99 3
('2014-01-06 08:10:00.000000+00:00', '2014-01-06 08:20:00.000000+00:00') 2 0 100 2
('2014-01-06 09:00:00.000000+00:00', '2014-01-06 09:10:00.000000+00:00') 7 1 79 6
('2014-01-06 10:00:00.000000+00:00', '2014-01-06 10:10:00.000000+00:00') 13 44 56 10
('2014-01-06 10:10:00.000000+00:00', '2014-01-06 10:20:00.000000+00:00') 14 44 43 1

Example: Using the HAVING Clause to Filter the MAX Function Results

The following example shows how the MAX function can be used with the HAVING clause to filter the results. In this case, the example filters out the rows which compute their result on less than three values.

The examples use the tables and data setup in Table and Data Definition for Time Series Aggregates Examples.

/*PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, MAX(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)
HAVING COUNT(*) >= 3
ORDER BY 3,2,1;

/*Non-PTI Table*/
SELECT $TD_TIMECODE_RANGE, $TD_GROUP_BY_TIME, BUOYID, MAX(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)
HAVING COUNT(*) >= 3
ORDER BY 3,2,1;

Result:

The results of both queries are identical so only one result set is shown.
TIMECODE_RANGE GROUP BY TIME (MINUTES(10)) BUOYID MAX (TEMPERATURE)
('2014-01-06 08:00:00.000000+00:00', '2014-01-06 08:10:00.000000+00:00') 1 0 99
('2014-01-06 09:00:00.000000+00:00', '2014-01-06 09:10:00.000000+00:00' 7 1 79
('2014-01-06 10:00:00.000000+00:00', '2014-01-06 10:10:00.000000+00:00') 13 44 56