mysqli::$insert_id

mysqli_insert_id

(PHP 5)

mysqli::$insert_id -- mysqli_insert_id — Returns the auto generated id used in the last query

说明

面向对象风格

mixed $mysqli->insert_id;

过程化风格

mixed mysqli_insert_id ( mysqli $link )

The mysqli_insert_id() function returns the ID generated by a query on a table with a column having the AUTO_INCREMENT attribute. If the last query wasn't an INSERT or UPDATE statement or if the modified table does not have a column with the AUTO_INCREMENT attribute, this function will return zero.

Note:
Performing an INSERT or UPDATE statement using the LAST_INSERT_ID() function will also modify the value returned by the mysqli_insert_id() function.

参数

link: 仅以过程化样式：由 mysqli_connect() 或 mysqli_init() 返回的链接标识。

返回值

The value of the AUTO_INCREMENT field that was updated by the previous query. Returns zero if there was no previous query on the connection or if the query did not update an AUTO_INCREMENT value.

Note:
If the number is greater than maximal int value, mysqli_insert_id() will return a string.

范例

Example #1 $mysqli->insert_id example

面向对象风格


<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

$mysqli->query("CREATE TABLE myCity LIKE City");

$query = "INSERT INTO myCity VALUES (NULL, 'Stuttgart', 'DEU', 'Stuttgart', 617000)";
$mysqli->query($query);

printf ("New Record has id %d.\n", $mysqli->insert_id);

/* drop table */
$mysqli->query("DROP TABLE myCity");

/* close connection */
$mysqli->close();
?>

过程化风格


<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

mysqli_query($link, "CREATE TABLE myCity LIKE City");

$query = "INSERT INTO myCity VALUES (NULL, 'Stuttgart', 'DEU', 'Stuttgart', 617000)";
mysqli_query($link, $query);

printf ("New Record has id %d.\n", mysqli_insert_id($link));

/* drop table */
mysqli_query($link, "DROP TABLE myCity");

/* close connection */
mysqli_close($link);
?>

以上例程会输出：

New Record has id 1.

PHP手册 - N: Returns the auto generated id used in the last query

用户评论:

fizzyorange at gmail dot com (01-Apr-2009 03:27)

Note that if you Call a MySQL stored procedure to insert a new record and then reference $db->insert_id; you will get 0 back, not the last inserted ID. It is therefore necessary to add a line to your MySQL Stored Procedure such as select last_insert_id() as intRecordKey; after the insert so that the query will return the new key value. Then in your php code you can use the following <?php $objInsertResult = $db->query($strSQL); $objInsertRow = $objInsertResult->fetch_object(); $intRecordKey = $objInsertRow->intRecordKey; ?> It would however be nice if $db->insert_id did return the last insert ID following a stored procedure call.

bert at nospam thinc dot nl (22-Jul-2008 04:58)

Watch out for the oo-style use of $db->insert_id. When the insert_id exceeds 2^31 (2147483648) fetching the insert id renders a wrong, too large number. You better use the procedural mysqli_insert_id( $db ) instead. [EDIT by danbrown AT php DOT net: This is another prime example of the limits of 32-bit signed integers.]

Nick Baicoianu (04-May-2007 09:10)

When running extended inserts on a table with an AUTO_INCREMENT field, the value of mysqli_insert_id() will equal the value of the *first* row inserted, not the last, as you might expect. <? //mytable has an auto_increment field $db->query("INSERT INTO mytable (field1,field2,field3) VALUES ('val1','val2','val3'), ('val1','val2','val3'), ('val1','val2','val3')"); echo $db->insert_id; //will echo the id of the FIRST row inserted ?>

will at phpfever dot com (21-Apr-2006 02:40)

I have received many statements that the insert_id property has a bug because it "works sometimes". Keep in mind that when using the OOP approach, the actual instantiation of the mysqli class will hold the insert_id. The following code will return nothing. <?php $mysqli = new mysqli('host','user','pass','db'); if ($result = $mysqli->query("INSERT INTO t (field) VALUES ('value');")) { echo 'The ID is: '.$result->insert_id; } ?> This is because the insert_id property doesn't belong to the result, but rather the actual mysqli class. This would work: <?php $mysqli = new mysqli('host','user','pass','db'); if ($result = $mysqli->query("INSERT INTO t (field) VALUES ('value');")) { echo 'The ID is: '.$mysqli->insert_id; } ?>

matix.bg a gmail (14-Mar-2006 10:56)

Some people are wondering how to get the ids of the rows inserted with loop. Here is it: <?php // stmt_init ... for (;;;) { // do some things... $stmt->execute(); $ids[] = $mysqli->insert_id; } ?>

alan at commondream dot net (03-Nov-2004 07:44)

I was having problems with getting the inserted id, and did a bit of testing. It ended up that if you commit a transaction before getting the last inserted id, it returns 0 every time, but if you get the last inserted id before committing the transaction, you get the correct value.