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Category: ASE: Functions: Aggregate Functions
sum()
The
aggregate function
sum()
computes the sum off all
values
in a
column
of a
table.
Syntax of the Aggregate Function sum()
sum( [ all | distinct ] expression )
The parameters of the Aggregate Function sum()
all
"all" calculates the sum of all values.
"all" is the default setting for the function sum().
distinct
"distinct" ignores duplicate values before summing up
"distinct" is an optional parameter.
expression
"expression"
usually serves as a placeholder for a column name in the function sum().
Usage of the Aggregate Function sum()
The function sum() can only be used for queries on
column names
which are declared as
numeric datatypes.
Queries on other datatypes return error messages.
NULL
values
are ignored in queries with sum().
The function sum() always converts the result of a query on
integer
data fields
into the
datatype
int.
Exception to this is the
bigint
datatype. sum() returns bigint
result sets
as bigint datatype.
To avoid
arithmetic overflow
errors,
variables,
to which the result of sum() is assigned, should be
declared
accordingly.
Example for the Aggregate Function sum()
Returns the sum of all values in the column column_name of the table table_name.
select sum(number_of_orders) from table_name
See also:
ASE T-SQL - Aggregate Functions,
avg(),
count(*),
count(),
count_big(),
max(),
min().
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