This chapter contains syntax diagrams, semantic descriptions,
rules, and examples of the use of the built-in functions listed
in the following tables.
For more information about functions, see Functions.
Aggregate functions
An aggregate function takes a set of values (like a column of data)
and returns a single value result from the set of values.
Scalar functions
A scalar function takes input argument(s) and returns
a single value result. A scalar function can be used wherever an expression
can be used.
Table functions
Table functions return columns of a table and resemble
a table created through a CREATE TABLE statement.