diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/catalogs.sgml | 44 |
1 files changed, 37 insertions, 7 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index cd3789f4ed2..cc42c5906ff 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/catalogs.sgml,v 2.125 2006/07/03 22:45:36 tgl Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/catalogs.sgml,v 2.126 2006/07/10 16:20:49 alvherre Exp $ --> <!-- Documentation of the system catalogs, directed toward PostgreSQL developers --> @@ -1640,6 +1640,30 @@ </row> <row> + <entry><structfield>relminxid</structfield></entry> + <entry><type>xid</type></entry> + <entry></entry> + <entry> + The minimum transaction ID present in all rows in this table. This + value is used to determine the database-global + <structname>pg_database</>.<structfield>datminxid</> value. + </entry> + </row> + + <row> + <entry><structfield>relvacuumxid</structfield></entry> + <entry><type>xid</type></entry> + <entry></entry> + <entry> + The transaction ID that was used as cleaning point as of the last vacuum + operation. All rows inserted, updated or deleted in this table by + transactions whose IDs are below this one have been marked as known good + or deleted. This is used to determine the database-global + <structname>pg_database</>.<structfield>datvacuumxid</> value. + </entry> + </row> + + <row> <entry><structfield>relacl</structfield></entry> <entry><type>aclitem[]</type></entry> <entry></entry> @@ -2022,21 +2046,27 @@ <entry><type>xid</type></entry> <entry></entry> <entry> - All rows inserted or deleted by transaction IDs before this one - have been marked as known committed or known aborted in this database. - This is used to determine when commit-log space can be recycled. + The transaction ID that was used as cleaning point as of the last vacuum + operation. All rows inserted or deleted by transaction IDs before this one + have been marked as known good or deleted. This + is used to determine when commit-log space can be recycled. + If InvalidTransactionId, then the minimum is unknown and can be + determined by scanning <structname>pg_class</>.<structfield>relvacuumxid</>. </entry> </row> <row> - <entry><structfield>datfrozenxid</structfield></entry> + <entry><structfield>datminxid</structfield></entry> <entry><type>xid</type></entry> <entry></entry> <entry> + The minimum transaction ID present in all tables in this database. All rows inserted by transaction IDs before this one have been relabeled with a permanent (<quote>frozen</>) transaction ID in this - database. This is useful to check whether a database must be vacuumed - soon to avoid transaction ID wrap-around problems. + database. This is useful to check whether a database must be + vacuumed soon to avoid transaction ID wrap-around problems. + If InvalidTransactionId, then the minimum is unknown and can be + determined by scanning <structname>pg_class</>.<structfield>relminxid</>. </entry> </row> |