Обсуждение: Problem with binary data transfer format of TEXT in 8.4

Hi all,

(Please redirect me to correct place if there is one).

I'm trying to implement proper binary data transfer in Database.HDBC.PostgreSQL Haskell library. This library is a wrapper around libpq.

I sorted out how to use paramFormats[] param of PQexecParams. I sorted out how to retrieve and properly unescape binary data when received with PQunescapeBytea.

Due to architecture of wrapper library I'm unable to make a difference between strings and binary data. It is all ByteString all over the place.

CREATE TABLE test( str TEXT, bytes BYTEA );

Works:

INSERT INTO test(bytes) VALUES (?)
with ["anything"]


SELECT bytes FROM test
returns ["anything"] correctly


Does not work:

INSERT INTO test(str) VALUES (?)
with ["anything"] sometimes fails with:

user error (SQL error: SqlError {seState = "08P01", seNativeError = 7, seErrorMsg = "execute: PGRES_FATAL_ERROR: ERROR:  insufficient data left in message\n"})

So it seems to me that putting string into database with binary format requires something more than just encoding it as UTF8 and stating its length in paramLengths[].


So the question is:

How do I transfer strings in binary format?

Note: I do not need binary format of anything else but UTF-8 encoded TEXT.
Note 2: I leave paramTypes[] as NULL.


Versions:

PostgreSQL 8.4
MacOSX 10.6
postgresql, bound to client: 8.4.9
Proxied driver: postgresql, bound to version: 3
Connected to server version: 80409

-- 
Gracjan