> + <entry role="catalog_table_entry"><para role="column_definition"> > + <structfield>subxact_count</structfield> <type>xid</type> > + </para> > + <para> > + The current backend's active subtransactions count.
subtransaction (no s) > + Set to true if current backend's subtransaction cache is overflowed. Say "has overflowed" > + if (local_beentry->subxact_count > 0) > + { > + values[30] = local_beentry->subxact_count; > + values[31] = local_beentry->subxact_overflowed; > + } > + else > + { > + nulls[30] = true; > + nulls[31] = true; > + } Why is the subxact count set to NULL instead of zero ? You added this to pg_stat_activity, which already has a lot of fields. We talked a few months ago about not adding more fields that weren't commonly used. https://www.postgresql.org/message-id/flat/20210426191811.sp3o77doinphyjhu%40alap3.anarazel.de#d96d0a116f0344301eead2676ea65b2e Since I think this field is usually not interesting to most users of pg_stat_activity, maybe this should instead be implemented as a function like pg_backend_get_subxact_status(pid). People who want to could use it like: SELECT * FROM pg_stat_activity psa, pg_backend_get_subxact_status(pid) sub; -- Justin