Remove debug_print_rel and replace usages with pprint

Going by c4a1933b4, b33ef397a and 05893712c (to name just a few), it seems
that maintaining debug_print_rel() is often forgotten.  In the case of
c4a1933b4, it was several years before anyone noticed that a path type
was not handled by debug_print_rel().  (debug_print_rel() is only
compiled when building with OPTIMIZER_DEBUG).

After a quick survey on the pgsql-hackers mailing list, nobody came
forward to admit that they use OPTIMIZER_DEBUG.  So to prevent any future
maintenance neglect, let's just remove debug_print_rel() and have
OPTIMIZER_DEBUG make use of pprint() instead (as suggested by Tom Lane).
If anyone wants to come forward to claim they make use of
OPTIMIZER_DEBUG in a way that they need debug_print_rel() then they have
around 10 months remaining in the v17 cycle where we could revert this.
If nobody comes forward in that time, then we can likely safely declare
debug_print_rel() as not worth keeping.

Discussion: https://postgr.es/m/CAApHDvoCdjo8Cu2zEZF4-AxWG-90S+pYXAnoDDa9J3xH-OrczQ@mail.gmail.com

diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 401290162600a174cfd7bdb7151ff3b2dedbe574..7af001feaacdca95af331384dd711ecc330ac875 100644 (file)
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -563,7 +563,7 @@ set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
    set_cheapest(rel);
 
 #ifdef OPTIMIZER_DEBUG
-   debug_print_rel(root, rel);
+   pprint(rel);
 #endif
 }
 
@@ -3504,7 +3504,7 @@ standard_join_search(PlannerInfo *root, int levels_needed, List *initial_rels)
            set_cheapest(rel);
 
 #ifdef OPTIMIZER_DEBUG
-           debug_print_rel(root, rel);
+           pprint(rel);
 #endif
        }
    }
@@ -4372,7 +4372,7 @@ generate_partitionwise_join_paths(PlannerInfo *root, RelOptInfo *rel)
            continue;
 
 #ifdef OPTIMIZER_DEBUG
-       debug_print_rel(root, child_rel);
+       pprint(child_rel);
 #endif
 
        live_children = lappend(live_children, child_rel);
@@ -4389,325 +4389,3 @@ generate_partitionwise_join_paths(PlannerInfo *root, RelOptInfo *rel)
    add_paths_to_append_rel(root, rel, live_children);
    list_free(live_children);
 }
-
-
-/*****************************************************************************
- *         DEBUG SUPPORT
- *****************************************************************************/
-
-#ifdef OPTIMIZER_DEBUG
-
-static void
-print_relids(PlannerInfo *root, Relids relids)
-{
-   int         x;
-   bool        first = true;
-
-   x = -1;
-   while ((x = bms_next_member(relids, x)) >= 0)
-   {
-       if (!first)
-           printf(" ");
-       if (x < root->simple_rel_array_size &&
-           root->simple_rte_array[x])
-           printf("%s", root->simple_rte_array[x]->eref->aliasname);
-       else
-           printf("%d", x);
-       first = false;
-   }
-}
-
-static void
-print_restrictclauses(PlannerInfo *root, List *clauses)
-{
-   ListCell   *l;
-
-   foreach(l, clauses)
-   {
-       RestrictInfo *c = lfirst(l);
-
-       print_expr((Node *) c->clause, root->parse->rtable);
-       if (lnext(clauses, l))
-           printf(", ");
-   }
-}
-
-static void
-print_path(PlannerInfo *root, Path *path, int indent)
-{
-   const char *ptype;
-   bool        join = false;
-   Path       *subpath = NULL;
-   int         i;
-
-   switch (nodeTag(path))
-   {
-       case T_Path:
-           switch (path->pathtype)
-           {
-               case T_SeqScan:
-                   ptype = "SeqScan";
-                   break;
-               case T_SampleScan:
-                   ptype = "SampleScan";
-                   break;
-               case T_FunctionScan:
-                   ptype = "FunctionScan";
-                   break;
-               case T_TableFuncScan:
-                   ptype = "TableFuncScan";
-                   break;
-               case T_ValuesScan:
-                   ptype = "ValuesScan";
-                   break;
-               case T_CteScan:
-                   ptype = "CteScan";
-                   break;
-               case T_NamedTuplestoreScan:
-                   ptype = "NamedTuplestoreScan";
-                   break;
-               case T_Result:
-                   ptype = "Result";
-                   break;
-               case T_WorkTableScan:
-                   ptype = "WorkTableScan";
-                   break;
-               default:
-                   ptype = "???Path";
-                   break;
-           }
-           break;
-       case T_IndexPath:
-           ptype = "IdxScan";
-           break;
-       case T_BitmapHeapPath:
-           ptype = "BitmapHeapScan";
-           break;
-       case T_BitmapAndPath:
-           ptype = "BitmapAndPath";
-           break;
-       case T_BitmapOrPath:
-           ptype = "BitmapOrPath";
-           break;
-       case T_TidPath:
-           ptype = "TidScan";
-           break;
-       case T_TidRangePath:
-           ptype = "TidRangePath";
-           break;
-       case T_SubqueryScanPath:
-           ptype = "SubqueryScan";
-           break;
-       case T_ForeignPath:
-           ptype = "ForeignScan";
-           break;
-       case T_CustomPath:
-           ptype = "CustomScan";
-           break;
-       case T_NestPath:
-           ptype = "NestLoop";
-           join = true;
-           break;
-       case T_MergePath:
-           ptype = "MergeJoin";
-           join = true;
-           break;
-       case T_HashPath:
-           ptype = "HashJoin";
-           join = true;
-           break;
-       case T_AppendPath:
-           ptype = "Append";
-           break;
-       case T_MergeAppendPath:
-           ptype = "MergeAppend";
-           break;
-       case T_GroupResultPath:
-           ptype = "GroupResult";
-           break;
-       case T_MaterialPath:
-           ptype = "Material";
-           subpath = ((MaterialPath *) path)->subpath;
-           break;
-       case T_MemoizePath:
-           ptype = "Memoize";
-           subpath = ((MemoizePath *) path)->subpath;
-           break;
-       case T_UniquePath:
-           ptype = "Unique";
-           subpath = ((UniquePath *) path)->subpath;
-           break;
-       case T_GatherPath:
-           ptype = "Gather";
-           subpath = ((GatherPath *) path)->subpath;
-           break;
-       case T_GatherMergePath:
-           ptype = "GatherMerge";
-           subpath = ((GatherMergePath *) path)->subpath;
-           break;
-       case T_ProjectionPath:
-           ptype = "Projection";
-           subpath = ((ProjectionPath *) path)->subpath;
-           break;
-       case T_ProjectSetPath:
-           ptype = "ProjectSet";
-           subpath = ((ProjectSetPath *) path)->subpath;
-           break;
-       case T_SortPath:
-           ptype = "Sort";
-           subpath = ((SortPath *) path)->subpath;
-           break;
-       case T_IncrementalSortPath:
-           ptype = "IncrementalSort";
-           subpath = ((SortPath *) path)->subpath;
-           break;
-       case T_GroupPath:
-           ptype = "Group";
-           subpath = ((GroupPath *) path)->subpath;
-           break;
-       case T_UpperUniquePath:
-           ptype = "UpperUnique";
-           subpath = ((UpperUniquePath *) path)->subpath;
-           break;
-       case T_AggPath:
-           ptype = "Agg";
-           subpath = ((AggPath *) path)->subpath;
-           break;
-       case T_GroupingSetsPath:
-           ptype = "GroupingSets";
-           subpath = ((GroupingSetsPath *) path)->subpath;
-           break;
-       case T_MinMaxAggPath:
-           ptype = "MinMaxAgg";
-           break;
-       case T_WindowAggPath:
-           ptype = "WindowAgg";
-           subpath = ((WindowAggPath *) path)->subpath;
-           break;
-       case T_SetOpPath:
-           ptype = "SetOp";
-           subpath = ((SetOpPath *) path)->subpath;
-           break;
-       case T_RecursiveUnionPath:
-           ptype = "RecursiveUnion";
-           break;
-       case T_LockRowsPath:
-           ptype = "LockRows";
-           subpath = ((LockRowsPath *) path)->subpath;
-           break;
-       case T_ModifyTablePath:
-           ptype = "ModifyTable";
-           break;
-       case T_LimitPath:
-           ptype = "Limit";
-           subpath = ((LimitPath *) path)->subpath;
-           break;
-       default:
-           ptype = "???Path";
-           break;
-   }
-
-   for (i = 0; i < indent; i++)
-       printf("\t");
-   printf("%s", ptype);
-
-   if (path->parent)
-   {
-       printf("(");
-       print_relids(root, path->parent->relids);
-       printf(")");
-   }
-   if (path->param_info)
-   {
-       printf(" required_outer (");
-       print_relids(root, path->param_info->ppi_req_outer);
-       printf(")");
-   }
-   printf(" rows=%.0f cost=%.2f..%.2f\n",
-          path->rows, path->startup_cost, path->total_cost);
-
-   if (path->pathkeys)
-   {
-       for (i = 0; i < indent; i++)
-           printf("\t");
-       printf("  pathkeys: ");
-       print_pathkeys(path->pathkeys, root->parse->rtable);
-   }
-
-   if (join)
-   {
-       JoinPath   *jp = (JoinPath *) path;
-
-       for (i = 0; i < indent; i++)
-           printf("\t");
-       printf("  clauses: ");
-       print_restrictclauses(root, jp->joinrestrictinfo);
-       printf("\n");
-
-       if (IsA(path, MergePath))
-       {
-           MergePath  *mp = (MergePath *) path;
-
-           for (i = 0; i < indent; i++)
-               printf("\t");
-           printf("  sortouter=%d sortinner=%d materializeinner=%d\n",
-                  ((mp->outersortkeys) ? 1 : 0),
-                  ((mp->innersortkeys) ? 1 : 0),
-                  ((mp->materialize_inner) ? 1 : 0));
-       }
-
-       print_path(root, jp->outerjoinpath, indent + 1);
-       print_path(root, jp->innerjoinpath, indent + 1);
-   }
-
-   if (subpath)
-       print_path(root, subpath, indent + 1);
-}
-
-void
-debug_print_rel(PlannerInfo *root, RelOptInfo *rel)
-{
-   ListCell   *l;
-
-   printf("RELOPTINFO (");
-   print_relids(root, rel->relids);
-   printf("): rows=%.0f width=%d\n", rel->rows, rel->reltarget->width);
-
-   if (rel->baserestrictinfo)
-   {
-       printf("\tbaserestrictinfo: ");
-       print_restrictclauses(root, rel->baserestrictinfo);
-       printf("\n");
-   }
-
-   if (rel->joininfo)
-   {
-       printf("\tjoininfo: ");
-       print_restrictclauses(root, rel->joininfo);
-       printf("\n");
-   }
-
-   printf("\tpath list:\n");
-   foreach(l, rel->pathlist)
-       print_path(root, lfirst(l), 1);
-   if (rel->cheapest_parameterized_paths)
-   {
-       printf("\n\tcheapest parameterized paths:\n");
-       foreach(l, rel->cheapest_parameterized_paths)
-           print_path(root, lfirst(l), 1);
-   }
-   if (rel->cheapest_startup_path)
-   {
-       printf("\n\tcheapest startup path:\n");
-       print_path(root, rel->cheapest_startup_path, 1);
-   }
-   if (rel->cheapest_total_path)
-   {
-       printf("\n\tcheapest total path:\n");
-       print_path(root, rel->cheapest_total_path, 1);
-   }
-   printf("\n");
-   fflush(stdout);
-}
-
-#endif                         /* OPTIMIZER_DEBUG */

diff --git a/src/include/optimizer/paths.h b/src/include/optimizer/paths.h
index 50bc3b503a65b1bb42fb0c28654882e307f88795..7b896d821e8961410a2fb04e130a9e04e698574f 100644 (file)
--- a/src/include/optimizer/paths.h
+++ b/src/include/optimizer/paths.h
@@ -63,10 +63,6 @@ extern void create_partial_bitmap_paths(PlannerInfo *root, RelOptInfo *rel,
 extern void generate_partitionwise_join_paths(PlannerInfo *root,
                                              RelOptInfo *rel);
 
-#ifdef OPTIMIZER_DEBUG
-extern void debug_print_rel(PlannerInfo *root, RelOptInfo *rel);
-#endif
-
 /*
  * indxpath.c
  *   routines to generate index paths