Aggregate. Returns the sum of squares of the independent expressions used in a linear regression model. Use the REGR_SXX function to evaluate the statistical validity of a regression model.
Syntax
REGR_SXX( dependent-expression , independent-expression )
Parameters| dependent-expression |
The variable that is affected by the independent variable. |
| independent-expression |
The variable that influences the outcome. |
This function converts its arguments to DOUBLE, performs the computation in double-precision floating point, and returns a DOUBLE as the result. If the function is applied to an empty set, then it returns NULL. The function is applied to the set of (dependent-expression and independent-expression) pairs after eliminating all pairs for which either dependent-expression or independent-expression is NULL. The function is computed simultaneously during a single pass through the data. After eliminating NULL values, the following computation is then made, where x represents the dependent-expression and y represents the independent-expression:
REGR_COUNT( x, y ) * VAR_POP( x )
SQL/2003 SQL foundation feature (T621) outside of core SQL.
With a GROUP BY clause:
SELECT REGR_SXX()( Salary, ( 2008 - YEAR( BirthDate ) ) )
FROM Employees
group by depart_ID
With a window:
SELECT REGR_SXX()( Salary, ( 2008 - YEAR( BirthDate ) ) )
FROM Employees
KEEP 10 ROWS