How to Correctly Sort Alphanumeric Data in MySQL's `ORDER BY` Clause?

MySQL 'Order By' - Sorting Alphanumeric Correctly

In MySQL, the 'Order By' clause sorts data based on the values of a specified column. However, when dealing with alphanumeric data, the default sorting method prioritizes the first digit, leading to incorrect ordering.

Understanding the Problem

For example, if we have the following data:

1
2
3
4
5
6
7
8
9
10
11
12

And we execute the query:

select * from table order by xxxxx asc

The result will be sorted as follows:

1
10
11
12
2
3
4
5
6
7
8
9

This is because the order is determined by the first digit, regardless of subsequent characters.

Solving the Problem

To sort alphanumeric data correctly, we can employ various tricks:

1. Alpha Numeric Sorting Using the Binary Way: This involves converting the alphanumeric values into binary and sorting them using the binary values.
2. Alpha Numeric Sorting Using the Cast Way: This approach casts the alphanumeric values as signed integers and sorts them using the integer representation.
3. Natural Sorting: This method sorts the data based on the natural order of the values, considering both digits and characters.
4. Sorting Numeric Values Mixed with Alphanumeric Values: In this case, we can convert the alphanumeric values to unsigned integers and sort them together with the numeric values.

Code Examples

Alpha Numeric Sorting Using the Bin Way:

SELECT 
tbl_column, 
BIN(tbl_column) AS binray_not_needed_column
FROM db_table
ORDER BY binray_not_needed_column ASC , tbl_column ASC

Natural Sorting:

SELECT alphanumeric, integer
       FROM sorting_test
       ORDER BY LENGTH(alphanumeric), alphanumeric  

Sorting Numeric Values Mixed with Alphanumeric Values:

SELECT version
FROM version_sorting
ORDER BY CAST(version AS UNSIGNED), version;

By employing these tricks, we can ensure that alphanumeric data is sorted correctly, maintaining the desired order of the items.

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