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:
SET collation_connection = 'utf8_general_ci';
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:
-
Database Collation Change: Execute the following command, replacing
your_database_name
with your actual database name:
ALTER DATABASE your_database_name CHARACTER SET utf8 COLLATE utf8_general_ci;
-
Table Collation Conversion: For each table affected by the collation mismatch, run this command (replace
your_table_name
accordingly):
ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;
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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