There seems to be an error with my SQL query. I keep getting this warning:
Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given in
which I'm pretty sure points to a syntax error, I found an SQL checker online and it said there's an error as well. I've been looking over this for days and I just can't seem to find what's wrong.
Here's the code:
function countReplies($cid, $scid, $tid, $mysqli){
$select = mysqli_query($mysqli, "SELECT category_id, subcatgory_id, topic_id FROM replies WHERE ".$cid." = category_id AND ".$scid." = subcategory_id AND ".$tid." = topic_id");
return mysqli_num_rows($select);
}
EDIT:
After using
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
This is the error I'm getting now:
Fatal error: Uncaught mysqli_sql_exception: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ''12' at line 6 in C:\\xampp\\htdocs(A)Book 2.0\\Bootstrap\\content_function.php:116 Stack trace: #0 C:\\xampp\\htdocs(A)Book 2.0\\Bootstrap\\content_function.php(116): mysqli_query(Object(mysqli), 'SELECT category...') #1 C:\\xampp\\htdocs(A)Book 2.0\\Bootstrap\\readtopic.php(55): countReplies('1', '2', '12', Object(mysqli)) #2 {main} thrown in C:\\xampp\\htdocs(A)Book 2.0\\Bootstrap\\content_function.php on line 116
i think you should be doing the ids / actual values you put inside of the query after the '=' sign. Like:
"SELECT category_id, subcatgory_id, topic_id FROM replies WHERE category_id = '.$cid.'
AND subcategory_id = '.$scid.' AND topic_id = '.$tid.';");
You have errors in your query :
field names must go to the left side of the « = » operand, values go to the right side
field values, when of type string (which, I assume, is the case in your query), must be enclosed in single quotes (or better yet, use bind parameters / this is the standard to pass variable values to a sql query).
Code :
$select = mysqli_query($mysqli,
"SELECT category_id, subcatgory_id, topic_id
FROM replies
WHERE
category_id = '".$cid."'
AND subcategory_id = '".$scid."'
AND topic_id = '".$tid."'"
);
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