Insert PHP Array Into MySQL With WHERE Clause - php

Question

I've already read Passing an array to a query using a WHERE clause which is basically what I am doing, but with strings instead of integers. I am having an issue with the WHERE clause.
$codes_imp = "'" . implode("','", $codes) . "'";
$passwords_imp = "'" . implode("','", $passwords) . "'";
$comments_imp = "'" . implode("','", $comments) . "'";
$set_pass_query = "INSERT INTO users (password, comments) VALUES ($passwords_imp, $comments_imp) WHERE Code IN ($codes_imp)";
When executed, the query looks like this:
INSERT INTO users (password, comments)
VALUES ('password1', 'password2', 'password3', 'comment1', 'comment2', 'comment3')
WHERE Code IN ('code1', 'code2', 'code3')
All columns in the table are of type VARCHAR. Clearly I have a syntax error (as it is telling me), but I am not sure how to construct this properly.

Answer 1

You are trying to constrain an INSERT query with a WHERE clause. That's a big no-no.
Either you want to UPDATE, or you need to drop the WHERE
What exactly are you trying to accomplish?

Answer 2

You need to use UPDATE and not INSERT, to alter existing db rows.
You could use a loop construct like the foreach loop.
E.g:
foreach($codes_imp as $key=>$code){
$query="UPDATE users SET password='$passwords_imp[$key]', comments='$comments_imp[$key]' WHERE Code='$code'"
[Code to execute the query goes here]
}
N.B: We need to use a loop construct because UPDATE queries can run only on one db row at a time.
Alternative method:
Instead of using loops you could use the CASE WHEN ELSE END syntax in Mysql.
To know how to use this, please refer:
https://stackoverflow.com/a/2528188/749232
http://www.kavoir.com/2009/05/mysql-update-multiple-rows-with-one-single-query.html