sql - duplicate rows MySQL -


hey using query this:

insert likes(           likes_memory_id,           likes_comment_id,           likes_owner_id,           likes_like  ) values (          :likes_memory_id,           :likes_comment_id,           :likes_owner_id,           :likes_like)

when ever user click button, query adds new row. query allows multiple time. prevent may use select statement , might succeed in 2 queries assue there better way it. (i made research if not exists statement didnt understand ) how avoid multiple likes?

the simplest create unique index on columns want unique;

create unique index uq_mem_own on likes(  likes_memory_id, likes_owner_id );

...and insert likes using insert ignore, insert value if it's not prevented index, otherwise ignore it;

insert ignore likes(   likes_memory_id,   likes_owner_id,   likes_like  ) values (  :likes_memory_id,   :likes_owner_id,   :likes_like)

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