In the following example, table T has 1 billion rows of weather data. It has 1 geometry column representing the point (latitude/longitude) of the observation, and these REAL columns:
- temperature
- air_pressure
- rainfall.
Use an SQL statement that invokes CALCMATRIX twice, once for the LOCAL phase and once for the COMBINE phase, as follows:
select * from CALCMATRIX( ON (
select 1 as p, X.* from CALCMATRIX( ON (select temperature, air_pressure, rainfall from T)
USING PHASE('LOCAL') )X )
HASH BY p
USING PHASE('COMBINE')
)Y;
The result set would be the SSCP matrix for the weather data. The following table shows the result set. n means the numeric result of the calculation.
| rownum | rowname | temperature | air_pressure | rainfall |
|---|---|---|---|---|
| 1 | temperature | n | n | n |
| 2 | air_pressure | n | n | n |
| 3 | rainfall | n | n | n |