The following bug has been logged online:

Bug reference: 2852
Logged by: Pavel Golub
Email address: pavel@microolap.com
PostgreSQL version: 8.x
Operating system: Windows XP
Description: User-defined type name begins with the underscore
character (_) can be created
Details:

Hello, pgsql-bugs.

Documentation says:
"User-defined type names cannot begin with the
underscore character (_) and can only be 62
characters long (or in general NAMEDATALEN - 2,
rather than the NAMEDATALEN - 1 characters
allowed for other names). Type names beginning
with underscore are reserved for
internally-created array type names. "

However, such SQL may be executed:

CREATE TYPE _my AS (id int4, id2 int4);

And then server treats it as an array type. Thus next SQL will be executed
too:

CREATE TABLE my_table(
my_arr my[]
);

Checked on PostgreSQL versions (Windows XP):
8.0.6
8.1.0
8.2.0

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I have applied the following documentaiton patch that states a leading
underscore "shouldn't" be used, rather than prohibited.

---------------------------------------------------------------------------

Pavel Golub wrote:
>
> The following bug has been logged online:
>
> Bug reference: 2852
> Logged by: Pavel Golub
> Email address: pavel@microolap.com
> PostgreSQL version: 8.x
> Operating system: Windows XP
> Description: User-defined type name begins with the underscore
> character (_) can be created
> Details:
>
> Hello, pgsql-bugs.
>
> Documentation says:
> "User-defined type names cannot begin with the
> underscore character (_) and can only be 62
> characters long (or in general NAMEDATALEN - 2,
> rather than the NAMEDATALEN - 1 characters
> allowed for other names). Type names beginning
> with underscore are reserved for
> internally-created array type names. "
>
> However, such SQL may be executed:
>
> CREATE TYPE _my AS (id int4, id2 int4);
>
> And then server treats it as an array type. Thus next SQL will be executed
> too:
>
> CREATE TABLE my_table(
> my_arr my[]
> );
>
> Checked on PostgreSQL versions (Windows XP):
> 8.0.6
> 8.1.0
> 8.2.0
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Have you searched our list archives?
>
> http://archives.postgresql.org

--
Bruce Momjian bruce@momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +


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Hello, Bruce.

Thanks for an answer. Are there any thoughts to insert check into
PostgreSQL code or we (developers) must take into account that UDT
with leading underscore may exist?

You wrote:

BM> I have applied the following documentaiton patch that states a leading
BM> underscore "shouldn't" be used, rather than prohibited.

BM> ---------------------------------------------------------------------------

BM> Pavel Golub wrote:
>>
>> The following bug has been logged online:
>>
>> Bug reference: 2852
>> Logged by: Pavel Golub
>> Email address: pavel@microolap.com
>> PostgreSQL version: 8.x
>> Operating system: Windows XP
>> Description: User-defined type name begins with the underscore
>> character (_) can be created
>> Details:
>>
>> Hello, pgsql-bugs.
>>
>> Documentation says:
>> "User-defined type names cannot begin with the
>> underscore character (_) and can only be 62
>> characters long (or in general NAMEDATALEN - 2,
>> rather than the NAMEDATALEN - 1 characters
>> allowed for other names). Type names beginning
>> with underscore are reserved for
>> internally-created array type names. "
>>
>> However, such SQL may be executed:
>>
>> CREATE TYPE _my AS (id int4, id2 int4);
>>
>> And then server treats it as an array type. Thus next SQL will be executed
>> too:
>>
>> CREATE TABLE my_table(
>> my_arr my[]
>> );
>>
>> Checked on PostgreSQL versions (Windows XP):
>> 8.0.6
>> 8.1.0
>> 8.2.0
>>
>> ---------------------------(end of broadcast)---------------------------
>> TIP 4: Have you searched our list archives?
>>
>> http://archives.postgresql.org




--
With best wishes,
Pavel mailtoavel@microolap.com


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