Is this the correct syntax for a mysql query

Question

I'm trying to pull an array from a mysql table and put it into an html table. It works successfully but when I try and add the restriction != null, no data is returned.

$query = mysqli_query($link, "select * from timetable Where id = $id and Subject != NULL");

Make sure the value of `$id` comes only from controlled sources. Otherwise the query is open for [SQL injection](http://stackoverflow.com/search?q=sql+injection). — axiac, Feb 06 '17 at 14:37

score 3 · Accepted Answer · edited Feb 06 '17 at 14:29

3

Don't use equality operator with NULL. You should use IS NULL or IS NOT NULL
Example:

Subject IS NOT NULL

edited Feb 06 '17 at 14:29

RMT

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answered Feb 06 '17 at 14:25

Rahul

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Not sure about the reasoning behind the downvote. Any? – Rahul Feb 06 '17 at 14:39

Is this the correct syntax for a mysql query

1 Answers1