Clarified LAST_INSERT_ID() behaviour for multi-row inserts.

+----+---------+

@end example

You can retrieve the used @code{AUTO_INCREMENT} key with the

@code{LAST_INSERT_ID()} SQL function or the @code{mysql_insert_id()} API

function.

Note: for a multi-row insert,

@code{LAST_INSERT_ID()}/@code{mysql_insert_id()} will actually return the

@code{AUTO_INCREMENT} key from the @strong{first} inserted row. This allows

multi-row inserts to be reproduced on other servers.

For MyISAM and BDB tables you can specify @code{AUTO_INCREMENT} on

secondary column in a multi-column key.  In this case the generated

value for the autoincrement column is calculated as

CREATE TABLE animals (

             grp ENUM('fish','mammal','bird') NOT NULL,

             id MEDIUMINT NOT NULL AUTO_INCREMENT,

             name CHAR(30) NOT NULL,

             PRIMARY KEY (grp,id)

             );

INSERT INTO animals (grp,name) VALUES("mammal","dog"),("mammal","cat"),

Note that in this case, the @code{AUTO_INCREMENT} value will be reused if you

delete the row with the biggest @code{AUTO_INCREMENT} value in any group.

You can get the used @code{AUTO_INCREMENT} key with the

@code{LAST_INSERT_ID()} SQL function or the @code{mysql_insert_id()} API

function.

@node Batch mode, Twin, Examples, Tutorial

@section Using @code{mysql} in Batch Mode