Finishing: View and modify mysql library, table, field encoding

View encoding

• Check database encoding.

show variables like '%char%';

• View table coding

show create table <表名>;

例：show create table user;

• View field codes

show full columns from <表名>;

例： show full column from user;

Modify the encoding format

• Modify database encoding format

alter database <数据库名> character set utf8mb4; 例：alter database db_user character set utf8mb4;

• Modify table encoding

alter table <表名> character set utf8mb4; 例：alter table user character set utf8mb4;

• Modify field encoding

ALTER TABLE <表名> MODIFY COLUMN <字段名> <字段类型> CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci; 例：ALTER TABLE comment MODIFY COLUMN content VARCHAR(512) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;