How to Fix the MySQL 'Illegal Mix of Collations' Error?

Troubleshooting the MySQL "Illegal Mix of Collations" Error

The dreaded "Illegal mix of collations" error in MySQL often occurs when comparing data with mismatched character sets or collations. This guide shows you how to resolve this issue, specifically addressing the conflict between 'latin1_swedish_ci' and 'utf8_general_ci'.

Immediate Solution

For a quick fix affecting only your current MySQL connection, use this command:

<code class="language-sql">SET collation_connection = 'utf8_general_ci';</code>

This temporarily adjusts the collation for the session.

Permanent Solution: Database and Table Adjustments

For a lasting solution, modify your database and table collations directly:

1. Database Collation Change: Execute the following command, replacing your_database_name with your actual database name:

<code class="language-sql">ALTER DATABASE your_database_name CHARACTER SET utf8 COLLATE utf8_general_ci;</code>

2. Table Collation Conversion: For each table affected by the collation mismatch, run this command (replace your_table_name accordingly):

<code class="language-sql">ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;</code>

By implementing these changes, you'll standardize your database and tables to use 'utf8_general_ci', eliminating future collation conflicts and ensuring consistent data handling.

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