GROUP BY statement in mysql

The GROUP BY statement is used in combined with the aggregate functions to group the result-set by one or more columns.

Aggregate functions:-aggregate functions are function whose return a single result.Such As MAX(),MIN().AVG(),SUM() and etc

MySQL GROUP BY Syntax

SELECT column_name, aggregate_function(column_name)
FROM table_name
WHERE condition
GROUP BY column_name

MySQL GROUP BY Example

We have the following "tbl_order" table:

Id OrderDate Price Customer
1 2008/11/12 1000 Vikram
2 2008/10/23 1600 Mohan
3 2008/09/02 700 Vikram
4 2008/09/03 300 Vikram
5 2008/08/30 2000 Rajeev
6 2008/10/04 100 Mohan

Now we want to find the total sum (total order) of each customer.

We will have to use the GROUP BY statement to group the customers.

We use the following SQL statement:

SELECT Customer,SUM(Price) FROM tbl_order
GROUP BY Customer

The result of following query will look like this:

Customer SUM(Price)
Vikram 2000
Mohan 1700
Rajeev 2000

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