Read only transactions - Commit or Rollback

Hello,

We have a database containing PostGIS MAP data, it is accessed mainly
via JDBC. There are multiple simultaneous read-only connections taken
from the JBoss connection pooling, and there usually are no active
writers. We use connection.setReadOnly(true).

Now my question is what is best performance-wise, if it does make any
difference at all:

Having autocommit on or off? (I presume "off")

Using commit or rollback?

Committing / rolling back occasionally (e. G. when returning the
connection to the pool) or not at all (until the pool closes the
connection)?

Thanks,
Markus

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Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

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