©
本文档使用
php.cn手册 发布
(PHP 5 >= 5.1.0)
pg_field_type_oid — Returns the type ID (OID) for the corresponding field number
$result
, int $field_number
) pg_field_type_oid() returns an integer containing the
OID of the base type of the given field_number
in the
given PostgreSQL result
resource.
You can get more information about the field type by querying PostgreSQL's pg_type system table using the OID obtained with this function. The PostgreSQL format_type() function will convert a type OID into an SQL standard type name.
Note:
If the field uses a PostgreSQL domain (rather than a basic type), it is the OID of the domain's underlying type that is returned, rather than the OID of the domain itself.
result
PostgreSQL query result resource, returned by pg_query() , pg_query_params() or pg_execute() (among others).
field_number
Field number, starting from 0.
The OID of the field's base type. FALSE
is returned on error.
Example #1 Getting information about fields
<?php
$dbconn = pg_connect ( "dbname=publisher" ) or die( "Could not connect" );
// Assume 'title' is a varchar type
$res = pg_query ( $dbconn , "select title from authors where author = 'Orwell'" );
echo "Title field type OID: " , pg_field_type_oid ( $res , 0 );
?>
以上例程会输出:
Title field type OID: 1043
[#1] mauroi at digbang dot com [2005-03-24 07:55:32]
This function can be used to improve the performance of your application.
pg_field_type() makes an internal query to the pg_type table and it can be really slow.
So if your application previously know the oids of your database, you can save the execution time of this query in every request.