Back-patch fix to not change pg_database.datvacuumxid or truncate CLOG

when an unprivileged user runs VACUUM.

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index a853344b9e418151837712522f8d41eb95b32e1a..5def52a9a2513ff5293193c188b102ec5b744e67 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.213.2.1 2002/04/02 05:12:00 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.213.2.2 2002/09/30 19:45:57 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -119,14 +119,14 @@ static TransactionId initialFreezeLimit;
 
 /* non-export function prototypes */
 static void vacuum_init(VacuumStmt *vacstmt);
-static void vacuum_shutdown(VacuumStmt *vacstmt);
+static void vacuum_shutdown(VacuumStmt *vacstmt, bool all_rels);
 static VRelList getrels(Name VacRelP, const char *stmttype);
 static void vac_update_dbstats(Oid dbid,
                                   TransactionId vacuumXID,
                                   TransactionId frozenXID);
 static void vac_truncate_clog(TransactionId vacuumXID,
                                  TransactionId frozenXID);
-static void vacuum_rel(Oid relid, VacuumStmt *vacstmt);
+static bool vacuum_rel(Oid relid, VacuumStmt *vacstmt);
 static void full_vacuum_rel(Relation onerel, VacuumStmt *vacstmt);
 static void scan_heap(VRelStats *vacrelstats, Relation onerel,
                  VacPageList vacuum_pages, VacPageList fraged_pages);
@@ -171,6 +171,7 @@ vacuum(VacuumStmt *vacstmt)
        const char *stmttype = vacstmt->vacuum ? "VACUUM" : "ANALYZE";
        NameData        VacRel;
        Name            VacRelName;
+       bool            all_rels;
        VRelList        vrl,
                                cur;
 
@@ -218,6 +219,9 @@ vacuum(VacuumStmt *vacstmt)
        else
                VacRelName = NULL;
 
+       /* Assume we are processing everything unless one table is mentioned */
+       all_rels = (VacRelName == NULL);
+
        /* Build list of relations to process (note this lives in vac_context) */
        vrl = getrels(VacRelName, stmttype);
 
@@ -236,13 +240,16 @@ vacuum(VacuumStmt *vacstmt)
        for (cur = vrl; cur != (VRelList) NULL; cur = cur->vrl_next)
        {
                if (vacstmt->vacuum)
-                       vacuum_rel(cur->vrl_relid, vacstmt);
+               {
+                       if (! vacuum_rel(cur->vrl_relid, vacstmt))
+                               all_rels = false; /* forget about updating dbstats */
+               }
                if (vacstmt->analyze)
                        analyze_rel(cur->vrl_relid, vacstmt);
        }
 
        /* clean up */
-       vacuum_shutdown(vacstmt);
+       vacuum_shutdown(vacstmt, all_rels);
 }
 
 /*
@@ -296,7 +303,7 @@ vacuum_init(VacuumStmt *vacstmt)
 }
 
 static void
-vacuum_shutdown(VacuumStmt *vacstmt)
+vacuum_shutdown(VacuumStmt *vacstmt, bool all_rels)
 {
        /* on entry, we are not in a transaction */
 
@@ -304,11 +311,11 @@ vacuum_shutdown(VacuumStmt *vacstmt)
        StartTransactionCommand();
 
        /*
-        * If we did a database-wide VACUUM, update the database's pg_database
-        * row with info about the transaction IDs used, and try to truncate
-        * pg_clog.
+        * If we completed a database-wide VACUUM without skipping any
+        * relations, update the database's pg_database row with info
+        * about the transaction IDs used, and try to truncate pg_clog.
         */
-       if (vacstmt->vacuum && vacstmt->vacrel == NULL)
+       if (vacstmt->vacuum && all_rels)
        {
                vac_update_dbstats(MyDatabaseId,
                                                   initialOldestXmin, initialFreezeLimit);
@@ -702,6 +709,11 @@ vac_truncate_clog(TransactionId vacuumXID, TransactionId frozenXID)
 /*
  *     vacuum_rel() -- vacuum one heap relation
  *
+ *             Returns TRUE if we actually processed the relation (or can ignore it
+ *             for some reason), FALSE if we failed to process it due to permissions
+ *             or other reasons.  (A FALSE result really means that some data
+ *             may have been left unvacuumed, so we can't update XID stats.)
+ *
  *             Doing one heap at a time incurs extra overhead, since we need to
  *             check that the heap exists again just before we vacuum it.      The
  *             reason that we do this is so that vacuuming can be spread across
@@ -710,13 +722,14 @@ vac_truncate_clog(TransactionId vacuumXID, TransactionId frozenXID)
  *
  *             At entry and exit, we are not inside a transaction.
  */
-static void
+static bool
 vacuum_rel(Oid relid, VacuumStmt *vacstmt)
 {
        LOCKMODE        lmode;
        Relation        onerel;
        LockRelId       onerelid;
        Oid                     toast_relid;
+       bool            result;
 
        /* Begin a transaction for vacuuming this relation */
        StartTransactionCommand();
@@ -736,7 +749,7 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt)
                                                          0, 0, 0))
        {
                CommitTransactionCommand();
-               return;
+               return true;                    /* okay 'cause no data there */
        }
 
        /*
@@ -768,7 +781,7 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt)
                         RelationGetRelationName(onerel));
                heap_close(onerel, lmode);
                CommitTransactionCommand();
-               return;
+               return false;
        }
 
        /*
@@ -797,6 +810,8 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt)
        else
                lazy_vacuum_rel(onerel, vacstmt);
 
+       result = true;                          /* did the vacuum */
+
        /* all done with this class, but hold lock until commit */
        heap_close(onerel, NoLock);
 
@@ -813,12 +828,17 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt)
         * statistics are totally unimportant for toast relations.
         */
        if (toast_relid != InvalidOid)
-               vacuum_rel(toast_relid, vacstmt);
+       {
+               if (! vacuum_rel(toast_relid, vacstmt))
+                       result = false;         /* failed to vacuum the TOAST table? */
+       }
 
        /*
         * Now release the session-level lock on the master table.
         */
        UnlockRelationForSession(&onerelid, lmode);
+
+       return result;
 }