MySQL Stored Procedure if statement

Question

DECLARE vote_id INT;
    select id from votes where votes.question_id = question_id and vote_type_id = 3 into vote_id;

    if vote_id is null then
      ...do A
    else
      ...do B
    end if;

the condition should be true and execute A part of code but always execute B part.
How to use select with if statement? Thank you very much.

Answer 1

尝试select id from votes where votes.question_id = question_id and votes.vote_type_id = 3 into vote_id;