(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
