Обсуждение: BUG #2395: Can't get right type oid by PQftype.

The following bug has been logged online:

Bug reference:      2395
Logged by:          wangshj
Email address:      wangshj@sduept.com
PostgreSQL version: 8.1.3
Operating system:   CentOS release 4.3 (Final)
Description:        Can't get right type oid  by PQftype.
Details:

I create a domain type testdomainoid.

CREATE DOMAIN testdomainoid int  CHECK(value >20);

In my database,the type oid of testdomainoid is 16385.But PQftype return 23
for testdomainoid's type oid.How could I get the testdomainoid's type oid.

--Creating a table use domain type.
CREATE TABLE test_domain_oid ( col testdomainoid );

--Insert a value.
INSERT INTO test_domain_oid VALUES (30);

//following is my test code.
#include <iostream>
#include "libpq-fe.h"
#include <sstream>

int main(int argc, char ** argv){
        PGconn * conn = PQconnectdb("");
        if( CONNECTION_OK != PQstatus(conn ) )
        {
                std::cout << "\nCan't connecte to db\n";
                return 0;
        }

        PGresult * r = PQexec( conn, "SELECT col FROM test_domain_oid " );
        if( PGRES_TUPLES_OK == PQresultStatus(r) )
        {
                Oid id = PQftype( r, 0 );
                int mod = PQfmod( r, 0 );
                std::cout<<"\noid: " << id<<"\nmod:" << mod <<std::endl;
        }
        else
        {
                std::cout << "\nQuery failed..\n";
                return 0;
        }

        PQclear( r );
        PQfinish( conn );
};

On Apr 14 06:30, wangshj wrote:
> In my database,the type oid of testdomainoid is 16385. But PQftype return 23
> for testdomainoid's type oid.

PQftype() returns the OID of the actual _type_ used in the domain.
Therefore, you get 23, OID of the int4/int type, in the above query.

> How could I get the testdomainoid's type oid.

Simply by querying pg_type catalog:

SELECT oid FROM pg_catalog.pg_type WHERE typname = 'testdomainoid';


Regards.

Volkan YAZICI <yazicivo@ttnet.net.tr> writes:
> On Apr 14 06:30, wangshj wrote:
>> In my database,the type oid of testdomainoid is 16385. But PQftype return 23
>> for testdomainoid's type oid.

> PQftype() returns the OID of the actual _type_ used in the domain.
> Therefore, you get 23, OID of the int4/int type, in the above query.

Yeah, this is considered a feature not a bug.  In fact the original
implementation just returned the domain's OID, and that was objected
to because most client programs wouldn't recognize it.

            regards, tom lane

Tom Lane 写道:

> > Yeah, this is considered a feature not a bug.  In fact the original
> > implementation just returned the domain's OID, and that was objected
> > to because most client programs wouldn't recognize it.
> >
> >
>
How to disable this feature ?