How can I check two conditions before inserting?

Question

I have three tables:

// Posts
+----+----------+---------------+-----------+
| id |  title   |    content    | id_author |
+----+----------+---------------+--         


        

Answer 1

INSERT INTO Votes (id_post,id_user)
SELECT p.id,u.id
FROM Posts p, Users u
WHERE p.id_user = :author
AND u.id = :user
AND u.active = 1 limit 1;

then you set parameter user equal to the current user id.

EDIT: I suppose id_user in table Votes must be the voter's id, not the author of the post (correct?), so I fixed the query eliminating the JOIN.

Answer 2

Use and with where

INSERT INTO Votes (id_post,id_user)
SELECT ?,?
FROM Posts p, Users u 
WHERE p.id_user = :author and u.active = 1 limit 1;

Answer 3

INSERT INTO Votes (id_post,id_user)
SELECT p.id, u.id
FROM Posts p
    INNER JOIN Users u ON 1 = 1
WHERE p.id_user = :author
    AND u.id = :current_user_id
    AND u.active = 1
LIMIT 1;