Order BY "ENUM field" in MYSQL

sql

database-management

mysql-optimization

enum-data-type

byAlex Kataev·Nov 10, 2024

SELECT * FROM your_table ORDER BY FIND_IN_SET(your_enum_column, 'value1,value2,value3');

Harness the power of MySQL's FIND_IN_SET() to effectuate sorting on an ENUM field. Specify the ENUM values in preferred order in a comma-separated list within the ORDER BY clause. This method is both efficient and concise, saving you from the complexity of additional case statements or joins.

Understanding ENUM sorting logic

MySQL ENUM fields are akin to a defined roadmap with specific stops – your permitted values. An important aspect of navigating this roadmap is knowing the sort order. The journey MySQL takes isn't based on the destination (values), but the path itself (index number).

Index-based sorting of ENUM values

An ENUM column in MySQL is a string object, the value of which is chosen from the list defined during the column specification. ENUM list starts with an index of 1. So, if the ENUM value 'email' is at position 1, 'mobile' at 2, then by default, 'email' comes before 'mobile'. In our daily lives, we generally take the shortest route first, and so does MySQL!

# Hold tight, MySQL sorting in progress!
SELECT * FROM your_table ORDER BY your_enum_column;

Sorting ENUM as strings

To have ENUM values sorted lexically, MySQL has to treat them as CHAR and not by their index. Here's where CAST() comes to play the role perfectly.

# Let's make MySQL read instead of count! 
SELECT * FROM your_table ORDER BY CAST(your_enum_column AS CHAR);

Roadmaps? Let's go off-road with custom sorting

In case you want to disregard the pre-defined paths and get adventurous, you can tailormade your ENUM sorting order. As in a treasure hunt, you decide the sequence with the FIELD() function:

# Going off-track with MySQL, 'cause why not?
SELECT * FROM your_table ORDER BY FIELD(your_enum_column, 'email', 'mobile', 'all', 'auto', 'nothing');

Want precise control? CASE statements to the rescue

Your own rules of sorting, your own game! With a CASE statement, control ENUM value sequence as per your whim:

# Who needs predefined paths when you have your own GPS (CASE)!
SELECT *
FROM your_table
ORDER BY 
  CASE your_enum_column
    WHEN 'email' THEN 1
    WHEN 'mobile' THEN 2
    WHEN 'all' THEN 3
    WHEN 'auto' THEN 4
    WHEN 'nothing' THEN 5
    ELSE 6
  END;

ENUM sorting nuances - the script behind the scenes

A challenge named NULL

You might have NULLs, and while sorting, they will always be first in line before any non-NULL values. They want to be first? Let them be!

# Hello NULLs, please be our opening act!
SELECT * FROM your_table ORDER BY your_enum_column;

Ascending or descending, it's your call

Like a roller coaster ride, sort ENUMs with CAST() or FIELD() using ASC (up-up-up!) or DESC (down-down-down!)

# Ready for the downhill rush?
SELECT * FROM your_table ORDER BY CAST(your_enum_column AS CHAR) DESC;

Remember, always verify your ENUM values in the database when using the FIELD() function. Cracked clues lead to treasures, here, accurate results!

Last but not least: Maximising ENUM effectiveness

The speed talk - Performance considerations

Indexed order is quicker than string comparison. But, if clarity is what you need, the lexical order is at your service.

The flip side of the ENUM coin - The pitfalls

Keep a check on the number of ENUM values you're dealing with. Too many cooks can spoil the broth, and so can too many ENUM values. Anticipate changes wisely because altering ENUM lists frequently is costly.