Re: Displaying text appears as hex data - Mailing list pgsql-general

On 8 February 2011 13:43, Thom Brown <thom@linux.com> wrote:
> On 8 February 2011 13:19, Michael <postgresql@encambio.com> wrote:
>>
>> Hello Thom,
>>
>> On Tues., Feb 08, 2011, Thom Brown wrote:
>>>On 8 February 2011 12:45, Michael <postgresql@encambio.com> wrote:
>>>> On Tues., Feb 08, 2011, Thom Brown wrote:
>>>>>On 8 February 2011 10:39, Michael wrote:
>>>>>> opensips=> select * from sip_trace;
>>>>>>  id | time_stamp | callid | traced_user | msg | method | ...
>>>>>>  1234 | 2011-02-03 | ... | | \x494e56495445207369703a...
>>>>>>
>>>>>> Others have said that when they use MySQL, the exact SQL command
>>>>>> as above results in ASCII text rather than hexadecimal, and this
>>>>>> is my goal as well.
>>>>>>
>>>>
>>>> opensips=> SELECT id, time_stamp, callid, traced_user,
>>>>           convert_from(msg, 'SQL_ASCII'), method FROM sip_trace;
>>>> ERROR:  function convert_from(text, unknown) does not exist
>>>> LINE 1: SELECT id, time_stamp, callid, traced_user, convert_from(msg...
>>>>                                                    ^
>>>>
>>>> The arrow in the last line indicates that 'convert_from' is not
>>>> correctly parsed.
>>>>
>>>My understanding was that your msg column was of type bytea.  Is this
>>>not the case?  Or is it a different column which needs converting?
>>>
>> The main developer has confirmed that the msg column is stored
>> as a BLOB, and I'm nearly sure that bytea is used in this case.
>> Yes, the correct column that is appearing in hex is called 'msg.'
>
> Well the function seems to think it's a text field.
>
>> Is the function 'convert_from' that you mentioned compiled into
>> the PostgreSQL server binary, or is it part of the template1 when
>> first created, or something else? It seems I'm missing it, right?
>
> No, you're probably not missing it.  It's complaining that a function
> with the given signature (text, unknown), doesn't exist.  It will work
> if it matches (bytea, name).  The error message being returned is
> saying that the msg field is actually a text field.
>
> Try:
>
> SELECT pg_typeof(msg) FROM sip_trace LIMIT 1;

Or if it really is text format:

SELECT id, time_stamp, callid, traced_user, convert_from(msg::bytea,
'SQL_ASCII'::name), method
FROM sip_trace;

But then that's less efficient than storing it as bytea and slower to query.

--
Thom Brown
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