How Can I Correctly Order Numbers Stored as Strings in MySQL?

The correct way to sort MySQL string numbers

Due to various limitations, numbers are sometimes stored in the VARCHAR data type in MySQL databases. However, when sorting data based on these values, characters take precedence over numeric values, causing numeric values ​​to be sorted incorrectly.

To solve this problem, you can explicitly convert the string value to an integer using the following syntax:

<code class="language-sql">SELECT col FROM yourtable
ORDER BY CAST(col AS UNSIGNED)</code>

This conversion forces the database to treat values ​​as integers, ensuring correct numerical ordering.

Alternatively, you can use mathematical operations that implicitly convert strings to integers, for example:

<code class="language-sql">SELECT col FROM yourtable
ORDER BY col + 0</code>

In this case, adding 0 forces MySQL to perform a numeric conversion.

Please note that MySQL converts strings from left to right. Strings that contain or begin with non-numeric characters are converted to 0, causing incorrect sorting. Therefore, you must ensure that the string value contains only numeric characters.

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