Re: [INTERFACES] JDBC - large objects

Update. This particular problem is resolved. Here what it was:

The failing code as per my original posting went something like this:

PreparedStatement statement = conn.prepareStatement("...");
: :
// add values to the prepared statement
: :
conn.setAutoCommit(false);
statement.executeUpdate("...");
conn.commit();

When I changed it to go something like this:

conn.setAutoCommit(false);
PreparedStatement statement = conn.prepareStatement("...");
: :
// add values to the prepared statement
: :
statement.executeUpdate("...");
conn.commit();

The "ERROR: lo_write: invalid large obj descriptor (0)" problem went away.

To summarize, autocommit needs to be turned off prior to statement creation.
(at least for prepared statements).

rc

At 02:03 AM 7/6/99 -0700, Rolland Crunk wrote:
>
>
>I am having some problem getting the jdbc driver to work properly with
>large objects using standard jdbc interfaces. The tables are pretty much
>standard relational tables except for one column that I serialize
>implementations of the java.security.acl.Acl as objects into.
>
>The error I get is: ERROR: lo_write: invalid large obj descriptor (0)
>
>This was the same error I got running the blobtest until I applied Tatsuo
>Ishii's
>patch I found in the mailing list archives. I tried the same thing in my code
>(turn on explicit transactions when storing a blob) but it doesn't seem to
>have any effect.
>
>I have tried defining the acl field in my create table statement as both:
>
> : :
> acl oid,
> : :
>
>and
>
> : :
> acl char[]
> : :
>
>And see same thing.
>
>The same (java) code runs fine using Oracle 8 and their thin driver.
>
>I guess what I need to know is: is what I am trying to do possible using
>PostgreSQL/JDBC without using the PostgreSQL extensions? (not an
>option for me). If so, what should I use for serialized columns in the
>create table sql statement? Can it be done without turning off autocommit?
>
>Thanks in advance for any help anyone can provide.
>
>Cordially,
>
>rc
>
>ps: My environment is:
>
> Solaris 2.7 (intel)
> jdk 1.2 (jdk 1.1 fares no better)
> PostgreSQL 6.5