MySQL MAX() function
MAX() function
MySQL MAX() function returns the maximum value of an expression.
This function is useful in -
- To identify the highest value within a column is crucial for understanding the upper limit of a dataset.
- When analyzing data, you might want to know the highest or peak value in a certain attribute.
- The MAX() function helps evaluate the highest performance metrics, such as maximum revenue, profits, or user engagement.
- Identifying the maximum value helps in assessing whether a process is operating within acceptable limits.
- When comparing performance against benchmarks, the MAX() function assists in determining how close or far data is from the best achieved results.
- In e-commerce or inventory management, determining the maximum order quantity helps in fulfilling customer demands efficiently.
- For critical decisions, knowing the maximum value in relevant data attributes can provide insights for strategic planning.
Syntax:
MAX(expr);
Where expr is an expression.
MySQL Version: 8.0
Example:
Sample table: book_mast
+---------+-------------------------------------+-------------+---------+--------+--------+------------+----------+---------+------------+ | book_id | book_name | isbn_no | cate_id | aut_id | pub_id | dt_of_pub | pub_lang | no_page | book_price | +---------+-------------------------------------+-------------+---------+--------+--------+------------+----------+---------+------------+ | BK001 | Introduction to Electrodynamics | 0000979001 | CA001 | AUT001 | P003 | 2001-05-08 | English | 201 | 85.00 | | BK002 | Understanding of Steel Construction | 0000979002 | CA002 | AUT002 | P001 | 2003-07-15 | English | 300 | 105.50 | | BK003 | Guide to Networking | 0000979003 | CA003 | AUT003 | P002 | 2002-09-10 | Hindi | 510 | 200.00 | | BK004 | Transfer of Heat and Mass | 0000979004 | CA002 | AUT004 | P004 | 2004-02-16 | English | 600 | 250.00 | | BK005 | Conceptual Physics | 0000979005 | CA001 | AUT005 | P006 | 2003-07-16 | NULL | 345 | 145.00 | | BK006 | Fundamentals of Heat | 0000979006 | CA001 | AUT006 | P005 | 2003-08-10 | German | 247 | 112.00 | | BK007 | Advanced 3d Graphics | 0000979007 | CA003 | AUT007 | P002 | 2004-02-16 | Hindi | 165 | 56.00 | | BK008 | Human Anatomy | 0000979008 | CA005 | AUT008 | P006 | 2001-05-17 | German | 88 | 50.50 | | BK009 | Mental Health Nursing | 0000979009 | CA005 | AUT009 | P007 | 2004-02-10 | English | 350 | 145.00 | | BK010 | Fundamentals of Thermodynamics | 0000979010 | CA002 | AUT010 | P007 | 2002-10-14 | English | 400 | 225.00 | ... ... ... +---------+-------------------------------------+-------------+---------+--------+--------+------------+----------+---------+------------+
Code:
-- This SQL query retrieves the maximum value of the book price from the book_mast table.
SELECT MAX(book_price) -- Selects the maximum value of the book price
FROM book_mast; -- Specifies the table from which to retrieve data (book_mast table)
Explanation:
- This SQL query retrieves data from the book_mast table.
- It selects the maximum value of the book price.
- Here's how the process works:
- The query uses the MAX() function to find the maximum value of the book price column.
- It retrieves this value from the book_mast table.
- Finally, the query returns the maximum value of the book price.
Relational Algebra Expression:
Relational Algebra Tree:
Explanation:
The above MySQL statement will return the maximum 'book_price' from 'book_mast' table.
Output:
mysql> SELECT MAX(book_price)
-> FROM book_mast;
+-----------------+
| MAX(book_price) |
+-----------------+
| 250.00 |
+-----------------+
1 row in set (0.00 sec)
PREV :
GROUP_CONCAT()
NEXT :
Max() with group by