首先,您需要确认您的数据库版本是否支持 utf8mb3_general_ci 排序规则。utf8mb3 是MySQL 早期版本中对 utf8 字符集的一种限制实现,它不支持完整的 Unicode 字符集,只支持最多3个字节的字符。而 utf8mb4 是utf8 的超集,支持完整的 Unicode 字符集,包括4个字节的字符。 如果您的数据库版本较新(如 MySQL 5.5...
mysql> show create table t1\G *** 1. row *** Table: t1 Create Table: CREATE TABLE `t1` ( `a` char(10) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci DEFAULT NULL, `b` varchar(10) CHARACTER SET latin2 COLLATE latin2_general_ci DEFAULT NULL, `c` char(10) COLLATE utf8mb4_...
WHERE TABLE_NAME COLLATE utf8mb3_bin = 'City' WHERE TABLE_NAME COLLATE utf8mb3_general_ci = 'city' WHERE UPPER(TABLE_NAME) = 'CITY' WHERE LOWER(TABLE_NAME) = 'city' Searches in INFORMATION_SCHEMA string columns for values that refer to INFORMATION_SCHEMA itself do use the utf8mb3_gene...
For a supplementary character,utf8mb4requires four bytes to store it, whereasutf8mb3cannot store the character at all. When convertingutf8mb3columns toutf8mb4, you need not worry about converting supplementary characters because there will be none. utf8mb4_general_ci 与utf8mb4_unicode_ci utf...
由于字符集utf8和utf8mb3是别名关系,因此排序规则utf8_general_ci和utf8mb3_general_ci是一样的。当您将character_set_server设置为utf8时,collation_server可能会被修改为utf8mb3_general_ci。 当仅修改collation_server参数时,系统会检查该参数取值与当前实例的character_set_server参数取值是否匹配。...
character_set_server utf8mb4 character_set_system utf8mb3 1. 2. 3. 4. 5. 6. 7. character_set_client 这里官方的解释是,客户端发送的语句时所用的字符集,这里的意思就是MySQL 或类MySQL的数据库产品,会认为在接受到客户端的发来的信息后,客户端的编码是 utf8mb4 . ...
String columns inINFORMATION_SCHEMAtables have a collation ofutf8mb3_general_ci, which is case-insensitive. However, for values that correspond to objects that are represented in the file system, such as databases and tables, searches inINFORMATION_SCHEMAstring columns can be case-sensitive or case...
Description Enable Emoji compatibility for values recorded inside the Table "core_config_data". Current default collation for field "value" is utf8mb3_general_ci This collation doesn't allow full EMOJI compatibility This is possible to c...
最后我像这样决定
_ci LIKE ?) OR (`configvalue` COLLATE utf8mb4_general_ci LIKE ?) ORDER BY `uid_lower` ASC LIMIT 500 OFFSET 500' with params ["%%", "%%", "%%"]: SQLSTATE[42000]: Syntax error or access violation: 1253 COLLATION 'utf8mb4_general_ci' is not vali...