verificar collation e charset aqui
modificar o default collation da base de dados:
SELECT DISTINCT concat('ALTER DATABASE ', TABLE_SCHEMA, ' CHARACTER SET utf8 COLLATE utf8_general_ci;') from information_schema.tables where TABLE_SCHEMA like 'database_name';
http://stackoverflow.com/questions/5906585/how-to-change-the-default-collation-of-a-database
modificar o default charset e collation de todas as tabelas na base de dados:
SELECT CONCAT("ALTER TABLE `", TABLE_NAME,"` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;") AS mySQL FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA="database_name" AND TABLE_TYPE="BASE TABLE";
http://stackoverflow.com/questions/10859966/how-to-convert-all-tables-in-database-to-one-collation
visualizar o collation de todas as colunas de todas as tabelas de todas as bases de dados:
SELECT TABLE_CATALOG, TABLE_SCHEMA, TABLE_NAME, COLUMN_NAME, COLLATION_NAME
FROM INFORMATION_SCHEMA.COLUMNS;
http://stackoverflow.com/questions/4948356/query-to-show-all-tables-and-their-collation