Oracle GROUP BY Clause
In Oracle GROUP BY clause is used with SELECT statement to collect data from multiple records and group the results by one or more columns.
Syntax:
Parameters:
expression1, expression2, … expression_n: It specifies the expressions that are not encapsulated within aggregate function. These expressions must be included in GROUP BY clause.
aggregate_function: It specifies the aggregate functions i.e. SUM, COUNT, MIN, MAX or AVG functions.
aggregate_expression: It specifies the column or expression on that the aggregate function is based on.
tables: It specifies the table from where you want to retrieve records.
conditions: It specifies the conditions that must be fulfilled for the record to be selected.
Oracle GROUP BY Example: (with SUM function)
Let’s take a table “salesdepartment”
Salesdepartment table:
Execute this query:
Output
The above example will show the total sales of every individual item.
Oracle GROUP BY Example: (with COUNT function)
Let’s take a table “customers”
Here we are creating a table named customers. This table doesn’t have any primary key.
Customer table:
Execute this query:
Output:
Oracle GROUP BY Example: (with MIN function)
Let?s take a table “employees”
Employees table:
Execute this query:
Output:
Oracle GROUP BY Example: (with MAX function)
In this example, we are using “employees” table that is given above.
Execute this query:
Output:
