It is recommended that you use the COUNT_BIG function when counting large result sets, the result might have more rows, or
there is a possibility of overflow. Otherwise, use the COUNT function, which has a maximum value of 2147483647.
Syntax 2 represents usage as a window function in a SELECT statement. As such, elements of window-spec can be specified either in the function syntax (inline), or with a WINDOW clause in the SELECT statement. See the window-spec definition in WINDOW clause.
For more information about using window functions in SELECT statements, including working examples, see Window functions.
SQL Anywhere does not support optional SQL/2008 feature F442, "Mixed column references in set functions". SQL Anywhere does
not permit the arguments of an aggregate function to include both a column reference from the query block containing the COUNT_BIG
function, combined with an outer reference.