MySQL修改字段编码

1.修改数据库编码

ALTER DATABASE ruoyi-vue-pro CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

2.修改数据表编码

-- 1.查看数据库默认编码
SELECT default_character_set_name, default_collation_name 
FROM information_schema.SCHEMATA 
WHERE schema_name = 'ruoyi-vue-pro';
-- 2.修改数据表的编码
ALTER TABLE 表名 CONVERT TO CHARACTER SET 字符集名称 COLLATE 排序规则名称;

3.修改数据表字段编码

-- 1. 查看数据库默认编码
SELECT default_character_set_name, default_collation_name 
FROM information_schema.SCHEMATA 
WHERE schema_name = 'ruoyi-vue-pro';

-- 2.查看表名及其存储引擎
SELECT 
    TABLE_NAME, 
    COLUMN_NAME, 
    concat(data_type,"(",CHARACTER_MAXIMUM_LENGTH,")") AS DATA_TYPE,
    CHARACTER_SET_NAME, 
    COLLATION_NAME
FROM 
    information_schema.COLUMNS
WHERE 
    TABLE_SCHEMA = 'ruoyi-vue-pro' and collation_name is not null and collation_name!="utf8mb4_general_ci"
    
-- 3.修改数据表字段编码    
ALTER TABLE  tb_test_col MODIFY COLUMN id varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;