RE: JDBC 2.0 Api compliancy and integration

Comments prefixed by PM:

--
Peter Mount
Enterprise Support Officer, Maidstone Borough Council
Email: petermount(at)maidstone(dot)gov(dot)uk
WWW: http://www.maidstone.gov.uk
All views expressed within this email are not the views of Maidstone Borough
Council

-----Original Message-----
From: Jason McIntosh [mailto:jwm05c(at)mizzou(dot)edu]
Sent: Thursday, October 26, 2000 5:38 PM
To: ML-Postgres-Interfaces
Subject: [INTERFACES] JDBC 2.0 Api compliancy and integration

Does anyone know the level of compliancy of Postgres with regards to
record locking. Specifically, which transaction levels it supports (if
any), and how well it supports them. I've been using the Oracle JDBC
drivers, and was saddened to find they only support
TRANSACTION_SERIALIZABLE and TRANSACTION_READ_COMMITTED, but the
READ_COMMITTED did very little in the way of record locking.

PM: We have some but not much. What was done was for the standard
extensions, so personally I'm not entirely sure how much is actually
implemented.

I'm trying to set it up so a java.sql.ResultSet can read all the records,
even those that are "locked", but when someone actually updates that
record, any attempts at modification or updates by that open ResultSet
fail. this is in specific reference to executeUpdate() and sending a SQL
Update string.

PM: I don't think we support this. Once a ResultSet has been read from the
backend, it has no communication with it, so there is no way for the
ResultSet to know of any changes to it's underlying records. Without
implementing a trigger to send a notify message, I'm not sure how we could
implement this transparently.

Thanks!
Jason McIntosh
Programmer/Analyst Specialist
University of Missouri, Columbia

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