**Why does MySQL DELETE with LIMIT and Offset Cause an Error?**

Error Encountered When Using MySQL DELETE Statement with LIMIT

Problem:

When attempting to delete rows from a table using a MySQL DELETE statement with a LIMIT clause, an error is encountered at the offset value in the LIMIT clause. The following query exemplifies the issue:

DELETE FROM `chat_messages` ORDER BY `timestamp` DESC LIMIT 20, 50;

The error message received at the offset value (50) is:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' 50' at line 1

Solution:

The error occurs because MySQL does not allow specifying an offset in the LIMIT clause of a DELETE statement. Consequently, we must resort to an alternative approach to achieve the desired result.

To delete specific rows from a table based on a range, we can use a subquery nested within the main DELETE query. The following modified query demonstrates this technique:

<code class="sql">DELETE FROM `chat_messages` 
WHERE `id` IN (
    SELECT `id` FROM (
        SELECT `id` FROM `chat_messages`
        ORDER BY `timestamp` DESC
        LIMIT 20, 50
    ) AS `x`
)</code>

In this query, the subquery within the IN clause retrieves the IDs of the rows to be deleted based on the specified range. Assuming the table has a primary key column named id, we can use it to identify each row uniquely.

Note: It's important to implement double nesting to avoid issues with MySQL's inability to select from currently modified tables.

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