pg_last_oid

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

pg_last_oid — 返回上一个对象的 oid

说明

pg_last_oid ( resource $result ) : int

pg_last_oid() 在上一条通过 pg_query() 发送的命令是 SQL INSERT 的情况下用来取得分配给所插入记录的 oid。如果存在有效的 oid 则返回一个正整数，如果出错或者上一条通过 pg_query() 发送的命令不是 INSERT 或者该 INSERT 失败则返回 FALSE。

从 PostgreSQL 7.2 版开始 OID 字段成为可选项。如果一个表中没有定义 OID 字段，程序员必须用 pg_result_status() 函数来检查记录是否被成功插入。

Note:

本函数以前的名字为 pg_getlastoid()。

参见 pg_query() 和 pg_result_status()。

User Contributed Notes

qeremy [atta] gmail [dotta] com 27-Jul-2012 02:11
Simply getting LAST_INSERT_ID;

<?php
// Note: waiting for "select" part from pg_query below.
// Note: separating the query parts using semicolons (;).

$qry = pg_query("
    INSERT INTO users (id,uname,upass,rep) VALUES (DEFAULT,'bubu','a981v',0.19);
    SELECT Currval('users_id_seq') LIMIT 1
");

// or
$qry = pg_query("
    INSERT INTO users (id,uname,upass,rep) VALUES (DEFAULT,'bubu','a981v',0.19) RETURNING Currval('users_id_seq')");

$fch = pg_fetch_row($qry);
print_r($fch);
?>

Array
(
    [0] => 3 -> Gotcha!
)
Jonathan Bond-Caron 30-May-2005 08:21
I'm sharing an elegant solution I found on the web (Vadim Passynkov):

CREATE RULE get_pkey_on_insert AS ON INSERT TO Customers DO SELECT currval('customers_customers_id_seq') AS id;

Every time you insert to the Customers table, postgreSQL will return a table with the id you just inserted. No need to worry about concurrency, the ressource is locked when the rule gets executed.

Note that in cases of multiple inserts:
INSERT INTO C1 ( ... ) ( SELECT * FROM C2);

we would return the id of the last inserted row.

For more info about PostgreSQL rules:
http://www.postgresql.org/docs/7.4/interactive/sql-createrule.html
julian at e2-media dot co dot nz 25-Aug-2003 11:21
The way I nuderstand it, each value is emitted by a sequence only ONCE. If you retrieve a number (say 12) from a sequence using nextval(), the sequence will advance and subsequent calls to nextval() will return further numbers (after 12) in the sequence.

This means that if you use nextval() to retrieve a value to use as a primary key, you can be guaranteed that no other calls to nextval() on that sequence will return the same value. No race conditions, no transactions required.

That's what sequences are *for* afaik :^)
a dot bardsley at lancs dot ac dot uk 15-May-2003 11:23
As pointed out on a busy site some of the above methods might actually give you an incorrect answer as another record is inserted inbetween your insert  and the select. To combat this put it into a transaction and dont commit till you have done all the work
dtutar at yore dot com dot tr 26-Apr-2003 07:15
This is very useful function :)

function sql_last_inserted_id($connection, $result, $table_name, $column_name) {
   $oid = pg_last_oid ( $result);
       $query_for_id = "SELECT $column_name FROM $table_name WHERE oid=$oid";
   $result_for_id = pg_query($connection,$query_for_id);
   if(pg_num_rows($result_for_id))
      $id=pg_fetch_array($result_for_id,0,PGSQL_ASSOC);
   return $id[$column_name];
}

Call after insert, simply ;)
webmaster at gamecrash dot net 03-Mar-2003 06:29
You could use this to get the last insert id...

CREATE TABLE test (
  id serial,
  something int not null
);

This creates the sequence test_id_seq. Now do the following after inserting something into table test:

INSERT INTO test (something) VALUES (123);
SELECT currval('test_id_seq') AS lastinsertid;

lastinsertid should contain your last insert id.