Edoardo Panfili <edoardo(at)aspix(dot)it> writes:
> It seems that if I put some delay between calls to the servlet all goes
> well. I can change lock level but ther is something wrong.
> Obviously I am doiung something wrong. To unlock the tables is not
> sufficient close the Statement and the Connection?
Um, possibly not, if you're using connection-pooling software ... and
even if you're not, I think closing the connection is asynchronous;
it'd be possible to establish a new connection before the old one has
terminated and released its locks.
Rather than closing the connection, I think you need to do something
explicit to commit your transaction.
regards, tom lane