Create a "sort support" interface API for faster sorting.

[postgresql] / src / backend / executor / nodeMergeAppend.c

diff --git a/src/backend/executor/nodeMergeAppend.c b/src/backend/executor/nodeMergeAppend.c
index 4ebe0cbe033372d6016c58d2aee7f2863ef3ba77..6065e2176ac118e135583fb1f0cdf72bb5f22252 100644 (file)
--- a/src/backend/executor/nodeMergeAppend.c
+++ b/src/backend/executor/nodeMergeAppend.c
@@ -38,10 +38,8 @@
 
 #include "postgres.h"
 
-#include "access/nbtree.h"
 #include "executor/execdebug.h"
 #include "executor/nodeMergeAppend.h"
-#include "utils/lsyscache.h"
 
 /*
  * It gets quite confusing having a heap array (indexed by integers) which
@@ -128,38 +126,18 @@ ExecInitMergeAppend(MergeAppend *node, EState *estate, int eflags)
         * initialize sort-key information
         */
        mergestate->ms_nkeys = node->numCols;
-       mergestate->ms_scankeys = palloc0(sizeof(ScanKeyData) * node->numCols);
+       mergestate->ms_sortkeys = palloc0(sizeof(SortSupportData) * node->numCols);
 
        for (i = 0; i < node->numCols; i++)
        {
-               Oid                     sortFunction;
-               bool            reverse;
-               int                     flags;
-
-               if (!get_compare_function_for_ordering_op(node->sortOperators[i],
-                                                                                                 &sortFunction, &reverse))
-                       elog(ERROR, "operator %u is not a valid ordering operator",
-                                node->sortOperators[i]);
-
-               /* We use btree's conventions for encoding directionality */
-               flags = 0;
-               if (reverse)
-                       flags |= SK_BT_DESC;
-               if (node->nullsFirst[i])
-                       flags |= SK_BT_NULLS_FIRST;
+               SortSupport     sortKey = mergestate->ms_sortkeys + i;
 
-               /*
-                * We needn't fill in sk_strategy or sk_subtype since these scankeys
-                * will never be passed to an index.
-                */
-               ScanKeyEntryInitialize(&mergestate->ms_scankeys[i],
-                                                          flags,
-                                                          node->sortColIdx[i],
-                                                          InvalidStrategy,
-                                                          InvalidOid,
-                                                          node->collations[i],
-                                                          sortFunction,
-                                                          (Datum) 0);
+               sortKey->ssup_cxt = CurrentMemoryContext;
+               sortKey->ssup_collation = node->collations[i];
+               sortKey->ssup_nulls_first = node->nullsFirst[i];
+               sortKey->ssup_attno = node->sortColIdx[i];
+
+               PrepareSortSupportFromOrderingOp(node->sortOperators[i], sortKey);
        }
 
        /*
@@ -298,44 +276,22 @@ heap_compare_slots(MergeAppendState *node, SlotNumber slot1, SlotNumber slot2)
 
        for (nkey = 0; nkey < node->ms_nkeys; nkey++)
        {
-               ScanKey         scankey = node->ms_scankeys + nkey;
-               AttrNumber      attno = scankey->sk_attno;
+               SortSupport     sortKey = node->ms_sortkeys + nkey;
+               AttrNumber      attno = sortKey->ssup_attno;
                Datum           datum1,
                                        datum2;
                bool            isNull1,
                                        isNull2;
-               int32           compare;
+               int                     compare;
 
                datum1 = slot_getattr(s1, attno, &isNull1);
                datum2 = slot_getattr(s2, attno, &isNull2);
 
-               if (isNull1)
-               {
-                       if (isNull2)
-                               continue;               /* NULL "=" NULL */
-                       else if (scankey->sk_flags & SK_BT_NULLS_FIRST)
-                               return -1;              /* NULL "<" NOT_NULL */
-                       else
-                               return 1;               /* NULL ">" NOT_NULL */
-               }
-               else if (isNull2)
-               {
-                       if (scankey->sk_flags & SK_BT_NULLS_FIRST)
-                               return 1;               /* NOT_NULL ">" NULL */
-                       else
-                               return -1;              /* NOT_NULL "<" NULL */
-               }
-               else
-               {
-                       compare = DatumGetInt32(FunctionCall2(&scankey->sk_func,
-                                                                                                 datum1, datum2));
-                       if (compare != 0)
-                       {
-                               if (scankey->sk_flags & SK_BT_DESC)
-                                       compare = -compare;
-                               return compare;
-                       }
-               }
+               compare = ApplySortComparator(datum1, isNull1,
+                                                                         datum2, isNull2,
+                                                                         sortKey);
+               if (compare != 0)
+                       return compare;
        }
        return 0;
 }