SQL Aggregate function
Each query in SQL returns filtered results of groups of values and also the field values. SQL provides aggregate functions to help with the summarization of large volumes of data.
This function can produce a single value for an entire group or table.
They operate on sets of rows and return results based on groups of rows.
The general syntax for most of the aggregate function is as follows:
aggregate_function( [ DISTINCT | ALL ] expression)
List of SQL Aggregate functions are :
|SQL Count function||The SQL COUNT function returns the number of rows in a table satisfying the criteria specified in the WHERE clause. It sets the number of rows or non NULL column values.|
|SQL Sum function||The SQL AGGREGATE SUM() function returns the sum of all selected column.|
|SQL Avg function||The SQL AVG function calculates the average value of a column of numeric type. It returns the average of all non NULL values|
|SQL Max function||The aggregate function SQL MAX() is used to find the maximum value or highest value of a certain column or expression. This function is useful to determine the largest of all selected values of a column.|
|SQL Min function||The aggregate function SQL MIN() is used to find the minimum value or lowest value of a column or expression. This function is useful to determine the smallest of all selected values of a column.|