Re: Inserting large BLOBs via JDBC - OutOfMemoryError

Make sure you have read and understand the limitations in postgres for
this approach. The java.sql.Blob support in the postgres jdbc driver
uses the postgres LargeObject API. There is a section in the postgres
jdbc documentation that explains the pros/cons of the LargeObject API as
compared to using the bytea datatype. If you can live with the
limitations, then this is a fine solution.

thanks,
--Barry

hhaag(at)gmx(dot)de wrote:

>There might be a workaround:
>
>>From JDBC 2.0 on, the interface java.sql.Blob allows to manipulate BLOBs.
>AbstractJdbc2Statement.setBlob() (code posted below) seems to create a BLOB
>upfront storing it in the database. The actual INSERT command will then only
>contain the OID, avoiding all memory problems.
>
>I'll let you know how it goes.
>
>
>
> public void setBlob(int i, Blob x) throws SQLException
> {
> InputStream l_inStream = x.getBinaryStream();
> int l_length = (int) x.length();
> LargeObjectManager lom = connection.getLargeObjectAPI();
> int oid = lom.create();
> LargeObject lob = lom.open(oid);
> OutputStream los = lob.getOutputStream();
> try
> {
> // could be buffered, but then the OutputStream returned by LargeObject
> // is buffered internally anyhow, so there would be no performance
> // boost gained, if anything it would be worse!
> int c = l_inStream.read();
> int p = 0;
> while (c > -1 && p < l_length)
> {
> los.write(c);
> c = l_inStream.read();
> p++;
> }
> los.close();
> }
> catch (IOException se)
> {
> throw new PSQLException("postgresql.unusual", se);
> }
> // lob is closed by the stream so don't call lob.close()
> setInt(i, oid);
> }
>
>
>
>
>