CREATE DEFINER=`root`@`%` FUNCTION `is_mixed`(str1 TEXT, str2 TEXT) RETURNS tinyint(4)
BEGIN
DECLARE ismixed TINYINT DEFAULT 0;
set ismixed:=(select concat(str1, ",") regexp concat(replace(str2,",",",|"), ","));
RETURN ismixed;
ENDcall:
select is_mixed("11,13","11,12,14,15,16")result: 1
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