"Error: Call to a member function rowCount() on a non-object" for INSERT

http://api.drupal.org/api/drupal/includes%21database%21query.inc/class/I...

When inserting data into the database, a queryobject (connection object) will be returned, where rowCount() doesn't exist.
It doesn't really make sense to count the amount of inserted rows, since you know the data that's being inserted.

It doesn't really make sense to count the amount of inserted rows, since you know the data that's being inserted.

I beg to differ.

Consider this pseudo-example:

<?php
$query = db_select('table1', 't')
  ->fields('t')
  ->condition('t.col1', $somevalue1)
  ->condition('t.col2', $somevalue2);

$result = db_insert('table2')
  ->from($query)
  ->execute();

$number_of_rows_inserted = $result->rowCount();
?>

This scenario is not unlikely. However, the above code of course won't work, since $result does not implement rowCount(). You could argue, that one could just run a countQuery() on the first $query object, but that would be inefficient, especially on large data sets.

Instead, we are currently forced to do:

<?php
$result = db_query("INSERT INTO {table2} SELECT * FROM {table1} t WHERE t.col1 = :somevalue1 AND t.col2 = :somevalue2", array(
  ':somevalue1' => $somevalue1,
  ':somevalue2' => $somevalue2,
));

$number_of_rows_inserted = $result->rowCount();
?>

Now this isn't really that bad. Except when you for example need something like a LIMIT clause in the select query, which may implemented differently for some backends as there's no SQL99 standard for this.

I'm therefore changing this ticket to a feature request.

My bad. This feature is actually present in another form, using the return option Database::RETURN_AFFECTED:

<?php
$query = db_select('table1', 't')
  ->fields('t')
  ->condition('t.col1', $somevalue1)
  ->condition('t.col2', $somevalue2);

$number_of_rows_inserted = db_insert('table2', array('return' => Database::RETURN_AFFECTED))
  ->from($query)
  ->execute();

?>