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SET @value := '"test1@test.com;test2@test.com"';
SELECT @value, CONCAT('"[', REPLACE(@value, ';', '", "'), ']"');
| @value | CONCAT('"[', REPLACE(@value, ';', '", "'), ']"') |
|---|---|
| "test1@test.com;test2@test.com" | "["test1@test.com", "test2@test.com"]" |