PHP 3 ways to get MySQL new record ID value _php Tutorial

First, use the statement:

Copy CodeThe code is as follows: mysql_query ("SELECT Max (ID) from T1", $link);
Using this method gives the highest ID value, which is the last value, but when a multilink thread, this maximum ID is not necessarily the self-increment ID value of the inserted data, and therefore does not apply to multithreading.

two, using the function: msyql_insert_id ();

In PHP, it is often necessary to remove the ID value from the inserted database, and there is exactly one function:
Copy CodeThe code is as follows:
<?php
Execute the statement that inserts the database
......
$getID =mysql_insert_id ();//$getID is the ID of the last record

Conditions of use for this function:
1. Assume that the field name is RecordID
2. Field properties must be set to: auto_increment
3. Use after adding data
$newID = mysql_insert_id ();
Get ID Value
?>

The PHP function, mysql_insert_id (), returns the value of the field defined by Auto_increment after the last insert query was executed.

When the system executes the INSERT, and then executes the SELECT, it may have been distributed to a different back-end server, and if you are using PHP programming, you should use MYSQL_INSERT_ID () to get the latest inserted ID, each time the insert ends, In fact, the corresponding AutoIncrement value has been calculated to return to PHP, you do not have to issue a separate query, directly with the mysql_insert_id ().
When a statement is inserted, it automatically returns the last ID (MySQL self-increment).
And this function is only useful for the current link, that is, it is multi-user-safe.
It is recommended to use this function;
Problem: When the ID is bigint, it does not work.

Third, use the query

Copy the Code code as follows: Msyql_query ("Select last_insert_id ()");
LAST_INSERT_ID () is a MySQL function that is also valid for the current link
This usage resolves the bigint type problem encountered in mysql_insert_id ()
Summarize:
It is recommended to use method two, in special cases, consider method three.

http://www.bkjia.com/PHPjc/824827.html www.bkjia.com true http://www.bkjia.com/PHPjc/824827.html techarticle one, the use of the statement: Copy code code is as follows: mysql_query ("SELECT Max (ID) from T1", $link); This method is used to obtain the maximum ID value, which is the last value, but when the multi-link thread ...

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