Returns the coefficient of determination for all non-null data pairs of the dependent and independent variable arguments.
For the REGR_R2 window function that performs a group, cumulative, or moving computation, see Window Aggregate Functions.
Computation
When there are fewer than two non-null data point pairs in the data used for the computation, then REGR_R2 returns NULL.
Division by zero returns NULL rather than an error.
ANSI Compliance
This statement is ANSI SQL:2011 compliant.