mysql怎么查询字符集命令

SHOW VARIABLES LIKE 'character_set_database';

SHOW CREATE TABLE your_table_name;

SHOW FULL COLUMNS FROM your_table_name;

SELECT DEFAULT_CHARACTER_SET_NAME FROM INFORMATION_SCHEMA.SCHEMATA;

SELECT TABLE_SCHEMA, TABLE_NAME, TABLE_COLLATION 
FROM INFORMATION_SCHEMA.TABLES 
WHERE TABLE_SCHEMA = 'your_database_name';

ALTER DATABASE your_database_name CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
ALTER TABLE your_table_name MODIFY your_column_name VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;