Converting Strings to Integers for Sorting in SQL

When dealing with mixed data types in a database column, such as integers and strings, it can lead to unexpected sorting issues. For instance, if you have a column that contains both integer values like 2 and string representations of numbers like '11', the default ordering may not behave as expected.

In this case, we want to sort these mixed data types in a specific order, with integers coming before strings. To achieve this, we can use the `TRY_CONVERT` function to convert the strings to integers, and then apply an `ORDER BY` clause based on this converted value.

Here is an example of how you can do this:

```

SELECT * FROM table_name ORDER BY

CASE WHEN TRY_CONVERT(int, col1) IS NULL THEN col1

ELSE RIGHT(Replicate('0', 20) + col1, 20)

END;

```

This code converts the `col1` column to an integer value using the `TRY_CONVERT` function. If the conversion is successful, it appends leading zeros to make sure the string representation of the integer is always 20 characters long. This ensures that integers are sorted before strings.

However, if you want to avoid converting strings to integers altogether and instead use a natural sorting order for strings, you can use the `CONVERT` function with the `USING` clause:

```

SELECT * FROM table_name ORDER BY

CONVERT(col1 USING latin1);

```

This code converts the `col1` column to the `latin1` character set, which is used by default in MariaDB for natural sorting.

In conclusion, when working with mixed data types in a database column, it's essential to consider how you want to sort these values. By using conversion functions like `TRY_CONVERT` or `CONVERT`, you can achieve the desired ordering and ensure that your data is sorted correctly.

Sql convert string to int order by