Group Functions: Part 1

Grouping Functions

Sheila has learned that there are several group functions that are available for use. All are ANSI-standard SQL functions.

* You can find the average of a group of values by using the AVG function.
* You can find the total of a group of values by using the SUM function.
* MAX finds a largest value. MIN returns a smallest value.
* STDDEV returns a standard deviation. VARIANCE returns the statistical variance.
* AVG , SUM , STDDEV , and VARIANCE can be used with numerical data only. You can use MAX and MIN on character, numeric, and date data types.
* You can use the COUNT function to return the number of values in a column.

Sheila will use the SQL GROUP functions in her SELECT statements to:

* Find the number of rows in a table
* Add the salaries
* Find the average, maximum, and minimum salaries
* Analyze salary information by department