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.
pg_field_type_oid
(PHP 5 >= 5.1.0)
pg_field_type_oid — Returns the type ID (OID) for the corresponding field number
说明
$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.
参数
-
result -
PostgreSQL query result resource, returned by pg_query(), pg_query_params() or pg_execute() (among others).
-
field_number -
Field number, starting from 0.
返回值
The OID of the field's base type. FALSE is returned on error.
范例
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
