PHP, Postgres help using RETURNING

regan_leah picture regan_leah · Oct 25, 2012 · Viewed 17.5k times · Source

I think I understand how PostgreSQL and RETURNING works - I've found many, many resources. If I'm catching on, it would look something like

"INSERT INTO table (column2, column3) VALUES ('value1', 'value2') RETURNING id;"

However, I can't find anything that helps me access this via PHP. When I thought I figured it out, I tried

$new_id = pg_query($dbc, "INSERT INTO table (column2, column3) ".
"VALUES ('value1', 'value2') RETURNING id;");
return $new_id;

But it returns NULL. I also tried executing and declaring the variable separately with one query. After looking for hours for the solution, I've settled on a max(id) SELECT statement/function, but it's still bothering me. Any help is greatly appreciated.

I'm using Postgres 8.4 and PHP 5.3.

Answer

greg picture greg · Oct 25, 2012

$new_id does not contain the id but it is a resource descriptor. You need to fetch the data from it as the query would be a SELECT, with pg_fetch_array($new_id) by example.

The RETURNING clause of PostgreSQL projects any fields of the inserted or modified rows ie INSERT|UPDATE … RETURNING id, field1, field2.