mysql - Need a trigger to prevent Unique input update from a table window -


i have frontend application windows table insert/update/delete rows in database table. have 1 unique column , i'm looking trigger prevent , give meaninful error user when trying insert duplicate.

create unique constraint in column. if user tries enter value present in table mysql error 1062 "duplicate entry....", @ time show user "value entered exist, please enter different value"


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