Re: [development] How to get the auto-increment value

28 Mar 2011

      Yep, you're doing it backwards, actually. :-)

In D6:

db_query("INSERT INTO {foo} (a, b) VALUES (%d, '%s')", 1, 'hi');
$cid = db_last_insert_id(); // The DB auto-generated this value.

In D7:

$cid = db_insert()
  ->fields(array(
    'a' => 1, 
    'b' => 'hi'
  ))
  ->execute();
// db_insert()->execute() returns the new auto-inc value automatically.

Note: In D7, you can do a multi-insert statement where several inserts run as 
a set.  That is faster than issuing separate queries, but the return value is 
then undefined and you do not have access to the last-insert-id.  Decide if 
you *actually* need to auto-generated ID right then and then pick multi-insert 
or not as appropriate.

As to your other question, the max number of rows, bear in mind that the 
number of rows may not correspond go the largest auto-inc value.  If you ever 
delete a row then the two will no longer match up.  Depending on which you 
care about, either of the following are valid (this is D7 syntax):

$num_records = db_query("SELECT COUNT(*) FROM {foo}")->fetchField();

$max_cid = db_query("SELECT MAX(cid) FROM {foo}")->fetchField();

Cheers.

--Larry Garfield

On Monday, March 28, 2011 5:59:14 am Austin Einter wrote:
...
Thanks Nancy.
Do you mean that in my code I should not put the value for "cid". That
means $lastid (in red) should be removed.
*$lastid = 0;
  for($delta = 0; $delta < $all_companies; $delta++)
  {
 $lastid = db_last_insert_id(rs_companies, cid) + 1;
      db_query(
    'INSERT INTO {rs_companies} ( cid, uid, prevcompany, joindate,
releasedate) '
      ."VALUES (%d, '%d', '%s', '%d', '%d')",
 $lastid,  *
*$user->uid*
Regards
Austin
On Mon, Mar 28, 2011 at 4:20 PM, nan wich <nan_wich@bellsouth.net> wrote:
...
You don't need to provide the value for an auto increment field.
"Db_last_insert_id()" is how you get the value *after* the insert, if you
need it at all.
*Nancy*
Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L.
King, Jr.
------------------------------
 *From:* Austin Einter
I have a table, where 'cid' field is of type "serial".
*$lastid = 0;
for($delta = 0; $delta < $all_companies; $delta++)
  {
$lastid = db_last_insert_id(rs_companies, cid) + 1;
db_query(
'INSERT INTO {rs_companies} ( cid, uid, prevcompany, joindate,
releasedate) '
."VALUES (%d, '%d', '%s', '%d', '%d')",
$lastid,  *