Fix thinko in previous patch to always update pg_class.reltuples/relpages.

I mis-simplified the test where ANALYZE decided if it could get away
without doing anything: under the new regime, that's never allowed.  Per
bug #6068 from Jeff Janes.  Back-patch to 8.4, just like previous patch.

diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 16169788576a479157900f9475c80c9744db0e1f..1e77752118c3eda3f97239b73c4e6b12de12c18a 100644 (file)
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -114,7 +114,6 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy)
    Relation   *Irel;
    int         nindexes;
    bool        hasindex;
-   bool        analyzableindex;
    VacAttrStats **vacattrstats;
    AnlIndexData *indexdata;
    int         targrows,
@@ -300,7 +299,6 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy)
    vac_open_indexes(onerel, AccessShareLock, &nindexes, &Irel);
    hasindex = (nindexes > 0);
    indexdata = NULL;
-   analyzableindex = false;
    if (hasindex)
    {
        indexdata = (AnlIndexData *) palloc0(nindexes * sizeof(AnlIndexData));
@@ -347,10 +345,7 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy)
                        thisdata->vacattrstats[tcnt] =
                            examine_attribute(Irel[ind], i + 1);
                        if (thisdata->vacattrstats[tcnt] != NULL)
-                       {
                            tcnt++;
-                           analyzableindex = true;
-                       }
                    }
                }
                thisdata->attr_cnt = tcnt;
@@ -358,16 +353,11 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy)
        }
    }
 
-   /*
-    * Quit if no analyzable columns.
-    */
-   if (attr_cnt <= 0 && !analyzableindex)
-       goto cleanup;
-
    /*
     * Determine how many rows we need to sample, using the worst case from
     * all analyzable columns.  We use a lower bound of 100 rows to avoid
-    * possible overflow in Vitter's algorithm.
+    * possible overflow in Vitter's algorithm.  (Note: that will also be
+    * the target in the corner case where there are no analyzable columns.)
     */
    targrows = 100;
    for (i = 0; i < attr_cnt; i++)
@@ -477,9 +467,6 @@ analyze_rel(Oid relid, VacuumStmt *vacstmt, BufferAccessStrategy bstrategy)
        }
    }
 
-   /* We skip to here if there were no analyzable columns */
-cleanup:
-
    /* If this isn't part of VACUUM ANALYZE, let index AMs do cleanup */
    if (!vacstmt->vacuum)
    {