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CREATE TABLE test (
txt1 VARCHAR(10) CHARACTER SET UTF8 COLLATE utf8_unicode_ci,
txt2 VARCHAR(10) CHARACTER SET UTF8 COLLATE utf8_general_ci
);
INSERT INTO test VALUES ('Проба', 'ба'), ('пера', 'ра');
Records: 2 Duplicates: 0 Warnings: 0
SELECT * FROM test WHERE txt1 = CONCAT('Про', txt2);
Illegal mix of collations (utf8mb3_unicode_ci,IMPLICIT) and (utf8mb3_general_ci,IMPLICIT) for operation '='
SELECT * FROM test WHERE txt1 = CONCAT('Про', txt2) COLLATE utf8mb3_unicode_ci;
| txt1 | txt2 |
|---|---|
| Проба | ба |