MySQL - 批量修改 字段charset和排序规则

Step1: 执行sql，按条件查询拼接 alter sql语句

SELECT
    CONCAT(
        'ALTER TABLE `',
        table_name,
        '` MODIFY `',
        column_name,
        '` ',
        DATA_TYPE,
        '(',
        CHARACTER_MAXIMUM_LENGTH,
        ') CHARACTER SET UTF8 COLLATE utf8_general_ci',
        (
            CASE
            WHEN IS_NULLABLE = 'NO' THEN
                ' NOT NULL'
            ELSE
                ''
            END
        ),
        ';'
    )
FROM
    information_schema. COLUMNS
WHERE
    TABLE_SCHEMA = 'database-name'
AND (DATA_TYPE = 'varchar' OR DATA_TYPE = 'char')
AND (
    CHARACTER_SET_NAME != 'utf8'
    OR COLLATION_NAME != 'utf8_general_ci'
);

step2: 全选并复制上述sql的执行结果，新建查询框执行得到的执行结果，OK!