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CREATE TABLE test (val VARCHAR(255) CHARACTER SET UTF8MB3 COLLATE utf8mb3_general_ci);
INSERT INTO test VALUES ('asdf'), ('фыва');
SHOW CREATE TABLE test;
SELECT val, HEX(val) FROM test;
Records: 2 Duplicates: 0 Warnings: 0
| Table | Create Table |
|---|---|
| test | CREATE TABLE `test` ( `val` varchar(255) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci |
| val | HEX(val) |
|---|---|
| asdf | 61736466 |
| фыва | D184D18BD0B2D0B0 |
ALTER TABLE test
MODIFY COLUMN val VARCHAR(255) CHARACTER SET latin1;
Incorrect string value: '\xD1\x84\xD1\x8B\xD0\xB2...' for column 'val' at row 2
ALTER TABLE test
MODIFY COLUMN val VARCHAR(255) CHARACTER SET UTF8MB4 COLLATE utf8mb4_general_ci;
SHOW CREATE TABLE test;
SELECT val, HEX(val) FROM test;
Records: 0 Duplicates: 0 Warnings: 0
| Table | Create Table |
|---|---|
| test | CREATE TABLE `test` ( `val` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci |
| val | HEX(val) |
|---|---|
| asdf | 61736466 |
| фыва | D184D18BD0B2D0B0 |