How to Sort MySQL Rows Numerically When IDs Contain Alphanumeric Text?

MySQL Query to Convert Partially Non-Numeric Text into Number

In MySQL, it's possible to extract the numeric portion from non-numeric text and convert it into a numeric data type to enable proper sorting.

Consider the case of a column containing identifiers that combine names and numbers in the format of "name-number." Sorting rows based on this column using the default character order results in an undesired order:

name-1
name-11
name-12
name-2

To resolve this issue, you can extract the numeric portion from the text using the SUBSTRING_INDEX() function:

SUBSTRING_INDEX(field,'-',-1)

This function extracts the substring after the last occurrence of the "-" character, effectively isolating the numeric portion.

Next, you can convert the extracted substring into an unsigned integer using the CONVERT() function:

CONVERT(SUBSTRING_INDEX(field,'-',-1),UNSIGNED INTEGER) AS num

This step transforms the character string into a numeric data type that can be used for numerical comparisons.

Finally, you can use the ORDER BY clause to sort the rows based on the extracted and converted numeric portion:

ORDER BY num

This query should produce the desired sorted order:

name-1
name-2
name-11
name-12

Note that this approach assumes that the non-numeric portion of the identifier will not contain any numbers. If this is not guaranteed, you may need to use more complex string manipulation techniques.

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