note 90981 added to function.pg-fetch-assoc

Beware! If your query returns multiple columns with the same names, only the right-most one will be contained in the result array. This can cause problems if you are using a combination of joins: For example: <?php // Let's say that 'pkey' is the primary-key colum for tables a and b (primary keys are never null) $res = pg_query("Select a.pkey, b.* FROM a LEFT JOIN b using (pkey)"); $data = pg_fetch_assoc($res); var_dump($data['pkey']) // Is actually b.pkey, may be NULL! ?> Both tables contain a column named 'pkey'. Now table 'b' is on the optional side of a LEFT JOIN, so b.pkey (implicitly included via 'b.*') may be NULL. The problem arises when you use pg_fetch_assoc(), there are two columns named 'pkey' but the result array can only contain one value per key -- in this case it will pick the one from table B instead of the one from table A, and since B is on the optional side of the left-join, $data['pkey'] may be NULL. So if you're expecting to retrieve the column from table A, you need to use a different pg_fetch() or rewrite your query to avoid ambiguity. ---- Server IP: 69.147.83.197 Probable Submitter: 76.2.25.104 ---- Manual Page -- http://www.php.net/manual/en/function.pg-fetch-assoc.php Edit -- https://master.php.net/note/edit/90981 Del: integrated -- https://master.php.net/note/delete/90981/integrated Del: useless -- https://master.php.net/note/delete/90981/useless Del: bad code -- https://master.php.net/note/delete/90981/bad+code Del: spam -- https://master.php.net/note/delete/90981/spam Del: non-english -- https://master.php.net/note/delete/90981/non-english Del: in docs -- https://master.php.net/note/delete/90981/in+docs Del: other reasons-- https://master.php.net/note/delete/90981 Reject -- https://master.php.net/note/reject/90981 Search -- https://master.php.net/manage/user-notes.php