Get the new record primary key ID from MySQL insert query?

Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key.

How do I get the query to output the value of the newly generated primary key item_id in the same query?

Currently I am running a second query to retrieve the id but this hardly seems like good practice considering this might produce the wrong result...

If this is not possible then what is the best practice to ensure I retrieve the correct id?

Solution 1:

You need to use the LAST_INSERT_ID() function: http://dev.mysql.com/doc/refman/5.0/en/information-functions.html#function_last-insert-id

Eg:

INSERT INTO table_name (col1, col2,...) VALUES ('val1', 'val2'...);
SELECT LAST_INSERT_ID();

This will get you back the PRIMARY KEY value of the last row that you inserted:

The ID that was generated is maintained in the server on a per-connection basis. This means that the value returned by the function to a given client is the first AUTO_INCREMENT value generated for most recent statement affecting an AUTO_INCREMENT column by that client.

So the value returned by LAST_INSERT_ID() is per user and is unaffected by other queries that might be running on the server from other users.

Solution 2:

BEWARE !! of LAST_INSERT_ID() if trying to return this primary key value within PHP.

I know this thread is not tagged PHP, but for anybody who came across this answer looking to return a MySQL insert id from a PHP scripted insert using standard mysql_query calls - it wont work and is not obvious without capturing SQL errors.

The newer mysqli supports multiple queries - which LAST_INSERT_ID() actually is a second query from the original.

IMO a separate SELECT to identify the last primary key is safer than the optional mysql_insert_id() function returning the AUTO_INCREMENT ID generated from the previous INSERT operation.

Solution 3:

From the LAST_INSERT_ID() documentation:

The ID that was generated is maintained in the server on a per-connection basis

That is if you have two separate requests to the script simultaneously they won't affect each others' LAST_INSERT_ID() (unless you're using a persistent connection perhaps).

Solution 4:

Here what you are looking for !!!

select LAST_INSERT_ID()

This is the best alternative of SCOPE_IDENTITY() function being used in SQL Server.

You also need to keep in mind that this will only work if Last_INSERT_ID() is fired following by your Insert query. That is the query returns the id inserted in the schema. You can not get specific table's last inserted id.

For more details please go through the link The equivalent of SQLServer function SCOPE_IDENTITY() in mySQL?