[Fwd: Re: Patch for - Change LIMIT/OFFSET to use int8] - Mailing list pgsql-patches

I sent this patch already.
Can somebody verify this patch?

Thanks
Dhanaraj
I have made the changes appropriately. The regression tests passed.
Since I do not have enough resources, I could not test for a large number.
It works for a small table. If anybody tests for int8 value, it is
appreciated.
Also, it gives the following error msg, when the input exceeds the int8
limit.

ERROR:  bigint out of range

I attach the patch. Pl. check it.
Thanks
Dhanaraj

Tom Lane wrote:

>Dhanaraj M <Dhanaraj.M@Sun.COM> writes:
>
>
>>I attach the patch for the following TODO item.
>>  SQL COMMAND
>>    * Change LIMIT/OFFSET to use int8
>>
>>
>
>This can't possibly be correct.  It doesn't even change the field types
>in struct LimitState, for example.  You've missed half a dozen places
>in the planner that would need work, too.
>
>            regards, tom lane
>
>---------------------------(end of broadcast)---------------------------
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*** ./src/backend/executor/nodeLimit.c.orig    Tue Jul 11 22:31:51 2006
--- ./src/backend/executor/nodeLimit.c    Wed Jul 12 00:46:11 2006
***************
*** 23,28 ****
--- 23,29 ----

  #include "executor/executor.h"
  #include "executor/nodeLimit.h"
+ #include "catalog/pg_type.h"

  static void recompute_limits(LimitState *node);

***************
*** 226,239 ****
  {
      ExprContext *econtext = node->ps.ps_ExprContext;
      bool        isNull;

-     if (node->limitOffset)
-     {
-         node->offset =
-             DatumGetInt32(ExecEvalExprSwitchContext(node->limitOffset,
-                                                     econtext,
-                                                     &isNull,
-                                                     NULL));
          /* Interpret NULL offset as no offset */
          if (isNull)
              node->offset = 0;
--- 227,251 ----
  {
      ExprContext *econtext = node->ps.ps_ExprContext;
      bool        isNull;
+       Oid type;
+
+        if (node->limitOffset)
+        {
+                  type = ((Const *) node->limitOffset->expr)->consttype;
+
+           if(type == INT8OID)
+               node->offset =
+               DatumGetInt64(ExecEvalExprSwitchContext(node->limitOffset,
+                                                        econtext,
+                                                        &isNull,
+                                                        NULL));
+           else
+                node->offset =
+                           DatumGetInt32(ExecEvalExprSwitchContext(node->limitOffset,
+                                                                                                           econtext,
+                                                                                                           &isNull,
+                                                                                                           NULL));

          /* Interpret NULL offset as no offset */
          if (isNull)
              node->offset = 0;
***************
*** 249,259 ****
      if (node->limitCount)
      {
          node->noCount = false;
!         node->count =
!             DatumGetInt32(ExecEvalExprSwitchContext(node->limitCount,
!                                                     econtext,
!                                                     &isNull,
!                                                     NULL));
          /* Interpret NULL count as no count (LIMIT ALL) */
          if (isNull)
              node->noCount = true;
--- 261,282 ----
      if (node->limitCount)
      {
          node->noCount = false;
!                 type = ((Const *) node->limitCount->expr)->consttype;
!
!                 if(type == INT8OID)
!              node->count =
!              DatumGetInt64(ExecEvalExprSwitchContext(node->limitCount,
!                                                       econtext,
!                                                       &isNull,
!                                                       NULL));
!          else
!              node->count =
!                          DatumGetInt32(ExecEvalExprSwitchContext(node->limitCount,
!                                                                                                          econtext,
!                                                                                                          &isNull,
!                                                                                                          NULL));
!
!
          /* Interpret NULL count as no count (LIMIT ALL) */
          if (isNull)
              node->noCount = true;
*** ./src/backend/optimizer/plan/createplan.c.orig    Tue Jul 11 22:32:31 2006
--- ./src/backend/optimizer/plan/createplan.c    Tue Jul 11 22:50:33 2006
***************
*** 2865,2871 ****
   */
  Limit *
  make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
!            int offset_est, int count_est)
  {
      Limit       *node = makeNode(Limit);
      Plan       *plan = &node->plan;
--- 2865,2871 ----
   */
  Limit *
  make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
!            int64 offset_est, int64 count_est)
  {
      Limit       *node = makeNode(Limit);
      Plan       *plan = &node->plan;
*** ./src/backend/optimizer/plan/planner.c.orig    Tue Jul 11 22:32:55 2006
--- ./src/backend/optimizer/plan/planner.c    Wed Jul 12 00:47:50 2006
***************
*** 61,67 ****
  static Plan *grouping_planner(PlannerInfo *root, double tuple_fraction);
  static double preprocess_limit(PlannerInfo *root,
                   double tuple_fraction,
!                  int *offset_est, int *count_est);
  static bool choose_hashed_grouping(PlannerInfo *root, double tuple_fraction,
                         Path *cheapest_path, Path *sorted_path,
                         double dNumGroups, AggClauseCounts *agg_counts);
--- 61,67 ----
  static Plan *grouping_planner(PlannerInfo *root, double tuple_fraction);
  static double preprocess_limit(PlannerInfo *root,
                   double tuple_fraction,
!                  int64 *offset_est, int64 *count_est);
  static bool choose_hashed_grouping(PlannerInfo *root, double tuple_fraction,
                         Path *cheapest_path, Path *sorted_path,
                         double dNumGroups, AggClauseCounts *agg_counts);
***************
*** 633,640 ****
  {
      Query       *parse = root->parse;
      List       *tlist = parse->targetList;
!     int            offset_est = 0;
!     int            count_est = 0;
      Plan       *result_plan;
      List       *current_pathkeys;
      List       *sort_pathkeys;
--- 633,640 ----
  {
      Query       *parse = root->parse;
      List       *tlist = parse->targetList;
!     int64            offset_est = 0;
!     int64            count_est = 0;
      Plan       *result_plan;
      List       *current_pathkeys;
      List       *sort_pathkeys;
***************
*** 1082,1088 ****
   */
  static double
  preprocess_limit(PlannerInfo *root, double tuple_fraction,
!                  int *offset_est, int *count_est)
  {
      Query       *parse = root->parse;
      Node       *est;
--- 1082,1088 ----
   */
  static double
  preprocess_limit(PlannerInfo *root, double tuple_fraction,
!                  int64 *offset_est, int64 *count_est)
  {
      Query       *parse = root->parse;
      Node       *est;
***************
*** 1107,1113 ****
              }
              else
              {
!                 *count_est = DatumGetInt32(((Const *) est)->constvalue);
                  if (*count_est <= 0)
                      *count_est = 1;        /* force to at least 1 */
              }
--- 1107,1114 ----
              }
              else
              {
!                      *count_est = DatumGetInt64(((Const *) est)->constvalue);
!
                  if (*count_est <= 0)
                      *count_est = 1;        /* force to at least 1 */
              }
***************
*** 1130,1136 ****
              }
              else
              {
!                 *offset_est = DatumGetInt32(((Const *) est)->constvalue);
                  if (*offset_est < 0)
                      *offset_est = 0;    /* less than 0 is same as 0 */
              }
--- 1131,1138 ----
              }
              else
              {
!                 *offset_est = DatumGetInt64(((Const *) est)->constvalue);
!
                  if (*offset_est < 0)
                      *offset_est = 0;    /* less than 0 is same as 0 */
              }
*** ./src/backend/parser/parse_clause.c.orig    Tue Jul 11 22:33:21 2006
--- ./src/backend/parser/parse_clause.c    Tue Jul 11 22:56:17 2006
***************
*** 1091,1097 ****

      qual = transformExpr(pstate, clause);

!     qual = coerce_to_integer(pstate, qual, constructName);

      /*
       * LIMIT can't refer to any vars or aggregates of the current query; we
--- 1091,1097 ----

      qual = transformExpr(pstate, clause);

!     qual = coerce_to_integer64(pstate, qual, constructName);

      /*
       * LIMIT can't refer to any vars or aggregates of the current query; we
*** ./src/backend/parser/parse_coerce.c.orig    Tue Jul 11 22:33:41 2006
--- ./src/backend/parser/parse_coerce.c    Wed Jul 12 00:58:57 2006
***************
*** 822,828 ****

  /* coerce_to_integer()
   *        Coerce an argument of a construct that requires integer input
!  *        (LIMIT, OFFSET, etc).  Also check that input is not a set.
   *
   * Returns the possibly-transformed node tree.
   *
--- 822,828 ----

  /* coerce_to_integer()
   *        Coerce an argument of a construct that requires integer input
!  *        Also check that input is not a set.
   *
   * Returns the possibly-transformed node tree.
   *
***************
*** 858,865 ****

      return node;
  }

-
  /* select_common_type()
   *        Determine the common supertype of a list of input expression types.
   *        This is used for determining the output type of CASE and UNION
--- 858,905 ----

      return node;
  }
+
+   /* coerce_to_integer64()
+    *              Coerce an argument of a construct that requires integer input
+    *              (LIMIT, OFFSET).  Also check that input is not a set.
+    *
+    * Returns the possibly-transformed node tree.
+    *
+    * As with coerce_type, pstate may be NULL if no special unknown-Param
+    * processing is wanted.
+    */
+   Node *
+   coerce_to_integer64(ParseState *pstate, Node *node,
+                                     const char *constructName)
+
+   {
+           Oid                     inputTypeId = exprType(node);
+
+           if (inputTypeId != INT8OID)
+           {
+                   node = coerce_to_target_type(pstate, node, inputTypeId,
+                                                                            INT8OID, -1,
+                                                                            COERCION_ASSIGNMENT,
+                                                                            COERCE_IMPLICIT_CAST);
+                   if (node == NULL)
+                           ereport(ERROR,
+                                           (errcode(ERRCODE_DATATYPE_MISMATCH),
+                           /* translator: first %s is name of a SQL construct, eg LIMIT */
+                                      errmsg("argument of %s must be type integer, not type %s",
+                                                     constructName, format_type_be(inputTypeId))));
+           }
+
+           if (expression_returns_set(node))
+                   ereport(ERROR,
+                                   (errcode(ERRCODE_DATATYPE_MISMATCH),
+                   /* translator: %s is name of a SQL construct, eg LIMIT */
+                                    errmsg("argument of %s must not return a set",
+                                                   constructName)));
+
+           return node;
+   }
+

  /* select_common_type()
   *        Determine the common supertype of a list of input expression types.
   *        This is used for determining the output type of CASE and UNION
*** ./src/include/nodes/execnodes.h.orig    Tue Jul 11 22:34:08 2006
--- ./src/include/nodes/execnodes.h    Tue Jul 11 22:59:43 2006
***************
*** 1328,1338 ****
      PlanState    ps;                /* its first field is NodeTag */
      ExprState  *limitOffset;    /* OFFSET parameter, or NULL if none */
      ExprState  *limitCount;        /* COUNT parameter, or NULL if none */
!     long        offset;            /* current OFFSET value */
!     long        count;            /* current COUNT, if any */
      bool        noCount;        /* if true, ignore count */
      LimitStateCond lstate;        /* state machine status, as above */
!     long        position;        /* 1-based index of last tuple returned */
      TupleTableSlot *subSlot;    /* tuple last obtained from subplan */
  } LimitState;

--- 1328,1338 ----
      PlanState    ps;                /* its first field is NodeTag */
      ExprState  *limitOffset;    /* OFFSET parameter, or NULL if none */
      ExprState  *limitCount;        /* COUNT parameter, or NULL if none */
!     int64        offset;            /* current OFFSET value */
!     int64        count;            /* current COUNT, if any */
      bool        noCount;        /* if true, ignore count */
      LimitStateCond lstate;        /* state machine status, as above */
!     int64        position;        /* 1-based index of last tuple returned */
      TupleTableSlot *subSlot;    /* tuple last obtained from subplan */
  } LimitState;

*** ./src/include/optimizer/planmain.h.orig    Tue Jul 11 22:36:57 2006
--- ./src/include/optimizer/planmain.h    Tue Jul 11 23:00:30 2006
***************
*** 55,61 ****
  extern Plan *materialize_finished_plan(Plan *subplan);
  extern Unique *make_unique(Plan *lefttree, List *distinctList);
  extern Limit *make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
!            int offset_est, int count_est);
  extern SetOp *make_setop(SetOpCmd cmd, Plan *lefttree,
             List *distinctList, AttrNumber flagColIdx);
  extern Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
--- 55,61 ----
  extern Plan *materialize_finished_plan(Plan *subplan);
  extern Unique *make_unique(Plan *lefttree, List *distinctList);
  extern Limit *make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
!            int64 offset_est, int64 count_est);
  extern SetOp *make_setop(SetOpCmd cmd, Plan *lefttree,
             List *distinctList, AttrNumber flagColIdx);
  extern Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
*** ./src/include/parser/parse_coerce.h.orig    Tue Jul 11 22:37:23 2006
--- ./src/include/parser/parse_coerce.h    Tue Jul 11 23:01:07 2006
***************
*** 58,64 ****
                    const char *constructName);
  extern Node *coerce_to_integer(ParseState *pstate, Node *node,
                    const char *constructName);
!
  extern Oid    select_common_type(List *typeids, const char *context);
  extern Node *coerce_to_common_type(ParseState *pstate, Node *node,
                        Oid targetTypeId,
--- 58,66 ----
                    const char *constructName);
  extern Node *coerce_to_integer(ParseState *pstate, Node *node,
                    const char *constructName);
! extern Node *coerce_to_integer64(ParseState *pstate, Node *node,
!                                     const char *constructName);
!
  extern Oid    select_common_type(List *typeids, const char *context);
  extern Node *coerce_to_common_type(ParseState *pstate, Node *node,
                        Oid targetTypeId,