Tom Lane 60b2444cc3 Add code to prevent transaction ID wraparound by enforcing a safe limit ... in GetNewTransactionId(). Since the limit value has to be computed before we run any real transactions, this requires adding code to database startup to scan pg_database and determine the oldest datfrozenxid. This can conveniently be combined with the first stage of an attack on the problem that the 'flat file' copies of pg_shadow and pg_group are not properly updated during WAL recovery. The code I've added to startup resides in a new file src/backend/utils/init/flatfiles.c, and it is responsible for rewriting the flat files as well as initializing the XID wraparound limit value. This will eventually allow us to get rid of GetRawDatabaseInfo too, but we'll need an initdb so we can add a trigger to pg_database.		2005-02-20 02:22:07 +00:00
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common	Change heap_modifytuple() to require a TupleDesc rather than a	2005-01-27 23:24:11 +00:00
gist	Marginal hack to merge adjacent ReleaseBuffer/ReadBuffer calls into	2005-02-05 19:38:58 +00:00
hash	Tag appropriate files for rc3	2004-12-31 22:04:05 +00:00
heap	Update copyrights that were missed.	2005-01-01 05:43:09 +00:00
index	Tag appropriate files for rc3	2004-12-31 22:04:05 +00:00
nbtree	Tag appropriate files for rc3	2004-12-31 22:04:05 +00:00
rtree	Fix memory leak in rtdosplit, per report from Clive Page.	2005-01-24 02:47:26 +00:00
transam	Add code to prevent transaction ID wraparound by enforcing a safe limit	2005-02-20 02:22:07 +00:00
Makefile	$Header: -> $PostgreSQL Changes ...	2003-11-29 19:52:15 +00:00