0001-Replace-OR-clause-to-ANY-expressions.diff

diff --git a/src/backend/optimizer/util/orclauses.c b/src/backend/optimizer/util/orclauses.c
index 6ef9d14b902..cbb187229fe 100644
--- a/src/backend/optimizer/util/orclauses.c
+++ b/src/backend/optimizer/util/orclauses.c
@@ -22,6 +22,10 @@
 #include "optimizer/optimizer.h"
 #include "optimizer/orclauses.h"
 #include "optimizer/restrictinfo.h"
+#include "utils/lsyscache.h"
+#include "parser/parse_expr.h"
+#include "parser/parse_coerce.h"
+#include "parser/parse_oper.h"
 
 
 static bool is_safe_restriction_clause_for(RestrictInfo *rinfo, RelOptInfo *rel);
@@ -29,6 +33,307 @@ static Expr *extract_or_clause(RestrictInfo *or_rinfo, RelOptInfo *rel);
 static void consider_new_or_clause(PlannerInfo *root, RelOptInfo *rel,
 								   Expr *orclause, RestrictInfo *join_or_rinfo);
 
+typedef struct OrClauseGroupEntry
+{
+	Node		   *node;
+	List		   *consts;
+	Oid				collation;
+	Oid				opno;
+	RestrictInfo   *rinfo;
+} OrClauseGroupEntry;
+
+int			or_transform_limit = 500;
+
+/*
+ * Pass through baserestrictinfo clauses and try to convert OR clauses into IN
+ * Return a modified clause list or just the same baserestrictinfo, if no
+ * changes have made.
+ * XXX: do not change source list of clauses at all.
+ */
+static List *
+transform_ors(PlannerInfo *root, List *baserestrictinfo)
+{
+	ListCell   *lc;
+	ListCell   *lc_cp;
+	List	   *modified_rinfo = NIL;
+	bool		something_changed = false;
+	List	   *baserestrictinfo_origin = list_copy(baserestrictinfo);
+
+	/*
+	 * Complexity of a clause could be arbitrarily sophisticated. Here, we will
+	 * look up only on the top level of clause list.
+	 * XXX: It is substantiated? Could we change something here?
+	 */
+	forboth (lc, baserestrictinfo, lc_cp, baserestrictinfo_origin)
+	{
+		RestrictInfo   *rinfo = lfirst_node(RestrictInfo, lc);
+		RestrictInfo   *rinfo_base = lfirst_node(RestrictInfo, lc_cp);
+		List		   *or_list = NIL;
+		ListCell	   *lc_eargs,
+					   *lc_rargs,
+					   *lc_args;
+		List		   *groups_list = NIL;
+		bool			change_apply = false;
+
+		if (!restriction_is_or_clause(rinfo) ||
+			list_length(((BoolExpr *) rinfo->clause)->args) < or_transform_limit)
+		{
+			/* Add a clause without changes */
+			modified_rinfo = lappend(modified_rinfo, rinfo);
+			continue;
+		}
+
+		/*
+		 * NOTE:
+		 * It is an OR-clause. So, rinfo->orclause is a BoolExpr node, contains
+		 * a list of sub-restrictinfo args, and rinfo->clause - which is the
+		 * same expression, made from bare clauses. To not break selectivity
+		 * caches and other optimizations, use both:
+		 * - use rinfos from orclause if no transformation needed
+		 * - use  bare quals from rinfo->clause in the case of transformation,
+		 * to create new RestrictInfo: in this case we have no options to avoid
+		 * selectivity estimation procedure.
+		 */
+		forboth(lc_eargs, ((BoolExpr *) rinfo->clause)->args,
+				lc_rargs, ((BoolExpr *) rinfo->orclause)->args)
+		{
+			Expr			   *orqual = (Expr *) lfirst(lc_eargs);
+			RestrictInfo	   *sub_rinfo;
+			Node			   *const_expr;
+			Node			   *non_const_expr;
+			ListCell		   *lc_groups;
+			OrClauseGroupEntry *gentry;
+
+			/* It may be one more boolean expression, skip it for now */
+			if (!IsA(lfirst(lc_rargs), RestrictInfo))
+			{
+				or_list = lappend(or_list, (void *) orqual);
+				continue;
+			}
+
+			sub_rinfo = lfirst_node(RestrictInfo, lc_rargs);
+
+			/* Check: it is an expr of the form 'F(x) oper ConstExpr' */
+			if (!IsA(orqual, OpExpr) ||
+				!(bms_is_empty(sub_rinfo->left_relids) ^
+				bms_is_empty(sub_rinfo->right_relids)) ||
+				contain_volatile_functions((Node *) orqual))
+			{
+				/* Again, it's not the expr we can transform */
+				or_list = lappend(or_list, (void *) orqual);
+				continue;
+			}
+
+			/*
+			* Detect the constant side of the clause. Recall non-constant
+			* expression can be made not only with Vars, but also with Params,
+			* which is not bonded with any relation. Thus, we detect the const
+			* side - if another side is constant too, the orqual couldn't be
+			* an OpExpr.
+			* Get pointers to constant and expression sides of the qual.
+			*/
+			const_expr =bms_is_empty(sub_rinfo->left_relids) ?
+												get_leftop(sub_rinfo->clause) :
+												get_rightop(sub_rinfo->clause);
+			non_const_expr = bms_is_empty(sub_rinfo->left_relids) ?
+												get_rightop(sub_rinfo->clause) :
+												get_leftop(sub_rinfo->clause);
+
+			if (!op_mergejoinable(((OpExpr *) sub_rinfo->clause)->opno, exprType(non_const_expr)))
+			{
+				/* And again, filter out non-equality operators */
+				or_list = lappend(or_list, (void *) orqual);
+				continue;
+			}
+
+			/*
+			 * At this point we definitely have a transformable clause.
+			 * Classify it and add into specific group of clauses, or create new
+			 * group.
+			 * TODO: to manage complexity in the case of many different clauses
+			 * (X1=C1) OR (X2=C2 OR) ... (XN = CN) we could invent something
+			 * like a hash table (htab key ???).
+			 */
+			foreach(lc_groups, groups_list)
+			{
+				OrClauseGroupEntry *v = (OrClauseGroupEntry *) lfirst(lc_groups);
+
+				Assert(v->node != NULL);
+
+				if (equal(v->node, non_const_expr))
+				{
+					v->consts = lappend(v->consts, const_expr);
+					non_const_expr = NULL;
+					break;
+				}
+			}
+
+			if (non_const_expr == NULL)
+				/*
+				 * The clause classified successfully and added into existed
+				 * clause group.
+				 */
+				continue;
+
+			/* New clause group needed */
+			gentry = palloc(sizeof(OrClauseGroupEntry));
+			gentry->node = non_const_expr;
+			gentry->consts = list_make1(const_expr);
+			gentry->rinfo = sub_rinfo;
+			groups_list = lappend(groups_list,  (void *) gentry);
+		}
+
+		if (groups_list == NIL)
+		{
+			/*
+			 * No any transformations possible with this rinfo, just add itself
+			 * to the list and go further.
+			 */
+			modified_rinfo = lappend(modified_rinfo, rinfo);
+			continue;
+		}
+
+		/* Let's convert each group of clauses to an IN operation. */
+
+		/*
+		 * Go through the list of groups and convert each, where number of
+		 * consts more than 1. trivial groups move to OR-list again
+		 */
+
+		foreach(lc_args, groups_list)
+		{
+			OrClauseGroupEntry *gentry = (OrClauseGroupEntry *) lfirst(lc_args);
+			ScalarArrayOpExpr  *saopexpr;
+			List			   *allexprs;
+			ArrayExpr		   *newa;
+			Oid				    scalar_type;
+			Oid					array_type;
+
+			Assert(list_length(gentry->consts) > 0);
+
+			if (list_length(gentry->consts) == 1)
+			{
+				/*
+				 * Only one element in the class. Return rinfo into the BoolExpr
+				 * args list unchanged.
+				 */
+				list_free(gentry->consts);
+				or_list = lappend(or_list, (void *) gentry->rinfo->clause);
+				continue;
+			}
+			if (list_length(gentry->consts) == 1)
+			{
+				/*
+				* Only one element in the class. Return rinfo into the BoolExpr
+				* args list unchanged.
+				*/
+				list_free(gentry->consts);
+				or_list = lappend(or_list, gentry->rinfo->clause);
+				continue;
+			}
+			allexprs = list_concat(list_make1(gentry->node), gentry->consts);
+			scalar_type = select_common_type(NULL, allexprs, NULL, NULL);
+
+			if (scalar_type != RECORDOID && OidIsValid(scalar_type))
+					array_type = get_array_type(scalar_type);
+			else
+					array_type = InvalidOid;
+			if (array_type != InvalidOid && scalar_type != InvalidOid)
+			{
+					/*
+					* OK: coerce all the right-hand non-Var inputs to the common
+					* type and build an ArrayExpr for them.
+					*/
+					List	   *aexprs;
+					ListCell *l;
+
+					aexprs = NIL;
+
+					foreach(l, gentry->consts)
+					{
+						Node	   *rexpr = (Node *) lfirst(l);
+
+						rexpr = coerce_to_common_type(NULL, rexpr,
+													scalar_type,
+													"IN");
+						aexprs = lappend(aexprs, rexpr);
+					}
+
+					newa = makeNode(ArrayExpr);
+					/* array_collid will be set by parse_collate.c */
+					newa->element_typeid = scalar_type;
+					newa->array_typeid = array_type;
+					newa->multidims = false;
+					newa->elements = aexprs;
+					newa->location = -1;
+
+					saopexpr =
+						(ScalarArrayOpExpr *)
+							make_scalar_array_op(NULL,
+												list_make1(makeString((char *) "=")),
+												true,
+												gentry->node,
+												(Node *) newa,
+												-1);
+					//saopexpr->inputcollid = exprInputCollation((Node *)gentry->rinfo->clause);
+
+					or_list = lappend(or_list, (void *) saopexpr);
+				change_apply = true;
+			}
+		}
+
+		if (!change_apply)
+		{
+			/*
+			 * Each group contains only one element - use rinfo as is.
+			 */
+			modified_rinfo = lappend(modified_rinfo, rinfo);
+			list_free(or_list);
+			list_free_deep(groups_list);
+			continue;
+		}
+
+		/*
+		 * Make a new version of the restriction. Remember source restriction
+		 * can be used in another path (SeqScan, for example).
+		 */
+
+		/* One more trick: assemble correct clause */
+		rinfo = make_restrictinfo(root,
+				  list_length(or_list) > 1 ? make_orclause(or_list) :
+											 (Expr *) linitial(or_list),
+				  rinfo->is_pushed_down,
+				  rinfo->has_clone,
+				  rinfo->is_clone,
+				  rinfo->pseudoconstant,
+				  rinfo->security_level,
+				  rinfo->required_relids,
+				  rinfo->incompatible_relids,
+				  rinfo->outer_relids);
+		rinfo->eval_cost=rinfo_base->eval_cost;
+		rinfo->norm_selec=rinfo_base->norm_selec;
+		rinfo->outer_selec=rinfo_base->outer_selec;
+		rinfo->left_bucketsize=rinfo_base->left_bucketsize;
+		rinfo->right_bucketsize=rinfo_base->right_bucketsize;
+		rinfo->left_mcvfreq=rinfo_base->left_mcvfreq;
+		rinfo->right_mcvfreq=rinfo_base->right_mcvfreq;
+		modified_rinfo = lappend(modified_rinfo, rinfo);
+		list_free_deep(groups_list);
+		something_changed = true;
+	}
+
+	/*
+	 * Check if transformation has made. If nothing changed - return
+	 * baserestrictinfo as is.
+	 */
+	if (something_changed)
+	{
+		return modified_rinfo;
+	}
+
+	list_free(modified_rinfo);
+	return baserestrictinfo;
+}
 
 /*
  * extract_restriction_or_clauses
@@ -93,6 +398,8 @@ extract_restriction_or_clauses(PlannerInfo *root)
 		if (rel->reloptkind != RELOPT_BASEREL)
 			continue;
 
+		rel->baserestrictinfo  = transform_ors(root, rel->baserestrictinfo);
+
 		/*
 		 * Find potentially interesting OR joinclauses.  We can use any
 		 * joinclause that is considered safe to move to this rel by the
diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c
index 16ec6c5ef02..a4f04d84021 100644
--- a/src/backend/utils/misc/guc_tables.c
+++ b/src/backend/utils/misc/guc_tables.c
@@ -2052,6 +2052,16 @@ struct config_int ConfigureNamesInt[] =
 		100, 1, MAX_STATISTICS_TARGET,
 		NULL, NULL, NULL
 	},
+	{
+		{"or_transform_limit", PGC_USERSET, QUERY_TUNING_OTHER,
+			gettext_noop("Transform a sequence of OR clauses to an IN expression."),
+			gettext_noop("The planner will replace clauses like 'x=c1 OR x=c2 .."
+						 "to the clause 'x IN (c1,c2,...)'")
+		},
+		&or_transform_limit,
+		500, 0, INT_MAX,
+		NULL, NULL, NULL
+	},
 	{
 		{"from_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
 			gettext_noop("Sets the FROM-list size beyond which subqueries "
diff --git a/src/include/parser/parse_expr.h b/src/include/parser/parse_expr.h
index 7d38ca75f7b..891e6a462b9 100644
--- a/src/include/parser/parse_expr.h
+++ b/src/include/parser/parse_expr.h
@@ -17,6 +17,7 @@
 
 /* GUC parameters */
 extern PGDLLIMPORT bool Transform_null_equals;
+extern PGDLLIMPORT int or_transform_limit;
 
 extern Node *transformExpr(ParseState *pstate, Node *expr, ParseExprKind exprKind);
 
diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index acfd9d1f4f7..a397137ecb6 100644
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -1883,6 +1883,150 @@ SELECT count(*) FROM tenk1
     10
 (1 row)
 
+SET or_transform_limit = 0;
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3 OR tenthous = 42);
+                               QUERY PLAN                               
+------------------------------------------------------------------------
+ Index Scan using tenk1_thous_tenthous on tenk1
+   Index Cond: ((thousand = 42) AND (tenthous = ANY (ARRAY[1, 3, 42])))
+(2 rows)
+
+SELECT * FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3 OR tenthous = 42);
+ unique1 | unique2 | two | four | ten | twenty | hundred | thousand | twothousand | fivethous | tenthous | odd | even | stringu1 | stringu2 | string4 
+---------+---------+-----+------+-----+--------+---------+----------+-------------+-----------+----------+-----+------+----------+----------+---------
+      42 |    5530 |   0 |    2 |   2 |      2 |      42 |       42 |          42 |        42 |       42 |  84 |   85 | QBAAAA   | SEIAAA   | OOOOxx
+(1 row)
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99);
+                                 QUERY PLAN                                  
+-----------------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on tenk1
+         Recheck Cond: ((hundred = 42) AND (thousand = ANY (ARRAY[42, 99])))
+         ->  BitmapAnd
+               ->  Bitmap Index Scan on tenk1_hundred
+                     Index Cond: (hundred = 42)
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: (thousand = ANY (ARRAY[42, 99]))
+(8 rows)
+
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99);
+ count 
+-------
+    10
+(1 row)
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3) OR thousand = 41;
+                                                        QUERY PLAN                                                         
+---------------------------------------------------------------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on tenk1
+         Recheck Cond: ((((thousand = 42) AND (tenthous = 1)) OR ((thousand = 42) AND (tenthous = 3))) OR (thousand = 41))
+         ->  BitmapOr
+               ->  BitmapOr
+                     ->  Bitmap Index Scan on tenk1_thous_tenthous
+                           Index Cond: ((thousand = 42) AND (tenthous = 1))
+                     ->  Bitmap Index Scan on tenk1_thous_tenthous
+                           Index Cond: ((thousand = 42) AND (tenthous = 3))
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: (thousand = 41)
+(11 rows)
+
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3) OR thousand = 41;
+ count 
+-------
+    10
+(1 row)
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 OR tenthous = 1 AND thousand = 42 OR tenthous = 1;
+                                            QUERY PLAN                                             
+---------------------------------------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on tenk1
+         Recheck Cond: ((thousand = 42) OR ((thousand = 42) AND (tenthous = 1)) OR (tenthous = 1))
+         ->  BitmapOr
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: (thousand = 42)
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: ((thousand = 42) AND (tenthous = 1))
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: (tenthous = 1)
+(10 rows)
+
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 OR tenthous = 1 AND thousand = 42 OR tenthous = 1;
+ count 
+-------
+    11
+(1 row)
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99 OR tenthous < 2) OR thousand = 41;
+                                                       QUERY PLAN                                                       
+------------------------------------------------------------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on tenk1
+         Recheck Cond: (((hundred = 42) AND ((thousand = 42) OR (thousand = 99) OR (tenthous < 2))) OR (thousand = 41))
+         ->  BitmapOr
+               ->  BitmapAnd
+                     ->  Bitmap Index Scan on tenk1_hundred
+                           Index Cond: (hundred = 42)
+                     ->  BitmapOr
+                           ->  Bitmap Index Scan on tenk1_thous_tenthous
+                                 Index Cond: (thousand = 42)
+                           ->  Bitmap Index Scan on tenk1_thous_tenthous
+                                 Index Cond: (thousand = 99)
+                           ->  Bitmap Index Scan on tenk1_thous_tenthous
+                                 Index Cond: (tenthous < 2)
+               ->  Bitmap Index Scan on tenk1_thous_tenthous
+                     Index Cond: (thousand = 41)
+(16 rows)
+
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99 OR tenthous < 2) OR thousand = 41;
+ count 
+-------
+    20
+(1 row)
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 41 OR thousand = 99 AND tenthous = 2);
+                                                      QUERY PLAN                                                       
+-----------------------------------------------------------------------------------------------------------------------
+ Aggregate
+   ->  Bitmap Heap Scan on tenk1
+         Recheck Cond: ((hundred = 42) AND (((thousand = 99) AND (tenthous = 2)) OR (thousand = ANY (ARRAY[42, 41]))))
+         ->  BitmapAnd
+               ->  Bitmap Index Scan on tenk1_hundred
+                     Index Cond: (hundred = 42)
+               ->  BitmapOr
+                     ->  Bitmap Index Scan on tenk1_thous_tenthous
+                           Index Cond: ((thousand = 99) AND (tenthous = 2))
+                     ->  Bitmap Index Scan on tenk1_thous_tenthous
+                           Index Cond: (thousand = ANY (ARRAY[42, 41]))
+(11 rows)
+
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 41 OR thousand = 99 AND tenthous = 2);
+ count 
+-------
+    10
+(1 row)
+
+RESET or_transform_limit;
 --
 -- Check behavior with duplicate index column contents
 --
diff --git a/src/test/regress/expected/guc.out b/src/test/regress/expected/guc.out
index 127c9532976..c052b113eea 100644
--- a/src/test/regress/expected/guc.out
+++ b/src/test/regress/expected/guc.out
@@ -861,7 +861,8 @@ SELECT name FROM tab_settings_flags
            name            
 ---------------------------
  default_statistics_target
-(1 row)
+ or_transform_limit
+(2 rows)
 
 -- Runtime-computed GUCs should be part of the preset category.
 SELECT name FROM tab_settings_flags
diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out
index 9b8638f286a..f22e4524099 100644
--- a/src/test/regress/expected/join.out
+++ b/src/test/regress/expected/join.out
@@ -4207,6 +4207,60 @@ select * from tenk1 a join tenk1 b on
                            Index Cond: (unique2 = 7)
 (19 rows)
 
+SET or_transform_limit = 0;
+explain (costs off)
+select * from tenk1 a join tenk1 b on
+  (a.unique1 = 1 and b.unique1 = 2) or
+  ((a.unique2 = 3 or a.unique2 = 7) and b.hundred = 4);
+                                                      QUERY PLAN                                                      
+----------------------------------------------------------------------------------------------------------------------
+ Nested Loop
+   Join Filter: (((a.unique1 = 1) AND (b.unique1 = 2)) OR (((a.unique2 = 3) OR (a.unique2 = 7)) AND (b.hundred = 4)))
+   ->  Bitmap Heap Scan on tenk1 b
+         Recheck Cond: ((unique1 = 2) OR (hundred = 4))
+         ->  BitmapOr
+               ->  Bitmap Index Scan on tenk1_unique1
+                     Index Cond: (unique1 = 2)
+               ->  Bitmap Index Scan on tenk1_hundred
+                     Index Cond: (hundred = 4)
+   ->  Materialize
+         ->  Bitmap Heap Scan on tenk1 a
+               Recheck Cond: ((unique1 = 1) OR (unique2 = 3) OR (unique2 = 7))
+               ->  BitmapOr
+                     ->  Bitmap Index Scan on tenk1_unique1
+                           Index Cond: (unique1 = 1)
+                     ->  Bitmap Index Scan on tenk1_unique2
+                           Index Cond: (unique2 = 3)
+                     ->  Bitmap Index Scan on tenk1_unique2
+                           Index Cond: (unique2 = 7)
+(19 rows)
+
+explain (costs off)
+select * from tenk1 a join tenk1 b on
+  (a.unique1 < 20 or a.unique1 = 3 or a.unique1 = 1 and b.unique1 = 2) or
+  ((a.unique2 = 3 or a.unique2 = 7) and b.hundred = 4);
+                                                                         QUERY PLAN                                                                          
+-------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Nested Loop
+   Join Filter: ((a.unique1 < 20) OR (a.unique1 = 3) OR ((a.unique1 = 1) AND (b.unique1 = 2)) OR (((a.unique2 = 3) OR (a.unique2 = 7)) AND (b.hundred = 4)))
+   ->  Seq Scan on tenk1 b
+   ->  Materialize
+         ->  Bitmap Heap Scan on tenk1 a
+               Recheck Cond: ((unique1 < 20) OR (unique1 = 3) OR (unique1 = 1) OR (unique2 = 3) OR (unique2 = 7))
+               ->  BitmapOr
+                     ->  Bitmap Index Scan on tenk1_unique1
+                           Index Cond: (unique1 < 20)
+                     ->  Bitmap Index Scan on tenk1_unique1
+                           Index Cond: (unique1 = 3)
+                     ->  Bitmap Index Scan on tenk1_unique1
+                           Index Cond: (unique1 = 1)
+                     ->  Bitmap Index Scan on tenk1_unique2
+                           Index Cond: (unique2 = 3)
+                     ->  Bitmap Index Scan on tenk1_unique2
+                           Index Cond: (unique2 = 7)
+(17 rows)
+
+RESET or_transform_limit;
 --
 -- test placement of movable quals in a parameterized join tree
 --
diff --git a/src/test/regress/expected/partition_prune.out b/src/test/regress/expected/partition_prune.out
index bb1223e2b13..ad4c4dae81e 100644
--- a/src/test/regress/expected/partition_prune.out
+++ b/src/test/regress/expected/partition_prune.out
@@ -101,6 +101,42 @@ explain (costs off) select * from lp where a is not null and (a = 'a' or a = 'c'
          Filter: ((a IS NOT NULL) AND ((a = 'a'::bpchar) OR (a = 'c'::bpchar)))
 (5 rows)
 
+SET or_transform_limit = 0;
+explain (costs off) select * from lp where a = 'a' or a = 'c';
+                  QUERY PLAN                   
+-----------------------------------------------
+ Append
+   ->  Seq Scan on lp_ad lp_1
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+   ->  Seq Scan on lp_bc lp_2
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+   ->  Seq Scan on lp_ef lp_3
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+   ->  Seq Scan on lp_g lp_4
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+   ->  Seq Scan on lp_null lp_5
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+   ->  Seq Scan on lp_default lp_6
+         Filter: (a = ANY ('{a,c}'::bpchar[]))
+(13 rows)
+
+explain (costs off) select * from lp where a is not null and (a = 'a' or a = 'c');
+                             QUERY PLAN                              
+---------------------------------------------------------------------
+ Append
+   ->  Seq Scan on lp_ad lp_1
+         Filter: ((a IS NOT NULL) AND (a = ANY ('{a,c}'::bpchar[])))
+   ->  Seq Scan on lp_bc lp_2
+         Filter: ((a IS NOT NULL) AND (a = ANY ('{a,c}'::bpchar[])))
+   ->  Seq Scan on lp_ef lp_3
+         Filter: ((a IS NOT NULL) AND (a = ANY ('{a,c}'::bpchar[])))
+   ->  Seq Scan on lp_g lp_4
+         Filter: ((a IS NOT NULL) AND (a = ANY ('{a,c}'::bpchar[])))
+   ->  Seq Scan on lp_default lp_5
+         Filter: ((a IS NOT NULL) AND (a = ANY ('{a,c}'::bpchar[])))
+(11 rows)
+
+RESET or_transform_limit;
 explain (costs off) select * from lp where a <> 'g';
              QUERY PLAN             
 ------------------------------------
@@ -671,6 +707,166 @@ explain (costs off) select * from rlp where (a = 1 and a = 3) or (a > 1 and a =
          Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
 (11 rows)
 
+SET or_transform_limit = 0;
+explain (costs off) select * from rlp where a = 1 or a = 7;
+                   QUERY PLAN                   
+------------------------------------------------
+ Append
+   Subplans Removed: 1
+   ->  Seq Scan on rlp2 rlp_1
+         Filter: (a = ANY ('{1,7}'::integer[]))
+(4 rows)
+
+explain (costs off) select * from rlp where a = 1 or b = 'ab';
+                      QUERY PLAN                       
+-------------------------------------------------------
+ Append
+   ->  Seq Scan on rlp1 rlp_1
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp2 rlp_2
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp3abcd rlp_3
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp4_1 rlp_4
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp4_2 rlp_5
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp4_default rlp_6
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp5_1 rlp_7
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp5_default rlp_8
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp_default_10 rlp_9
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp_default_30 rlp_10
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp_default_null rlp_11
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+   ->  Seq Scan on rlp_default_default rlp_12
+         Filter: ((a = 1) OR ((b)::text = 'ab'::text))
+(25 rows)
+
+explain (costs off) select * from rlp where a > 20 and a < 27;
+               QUERY PLAN                
+-----------------------------------------
+ Append
+   ->  Seq Scan on rlp4_1 rlp_1
+         Filter: ((a > 20) AND (a < 27))
+   ->  Seq Scan on rlp4_2 rlp_2
+         Filter: ((a > 20) AND (a < 27))
+(5 rows)
+
+explain (costs off) select * from rlp where a = 29;
+          QUERY PLAN          
+------------------------------
+ Seq Scan on rlp4_default rlp
+   Filter: (a = 29)
+(2 rows)
+
+explain (costs off) select * from rlp where a >= 29;
+                 QUERY PLAN                  
+---------------------------------------------
+ Append
+   ->  Seq Scan on rlp4_default rlp_1
+         Filter: (a >= 29)
+   ->  Seq Scan on rlp5_1 rlp_2
+         Filter: (a >= 29)
+   ->  Seq Scan on rlp5_default rlp_3
+         Filter: (a >= 29)
+   ->  Seq Scan on rlp_default_30 rlp_4
+         Filter: (a >= 29)
+   ->  Seq Scan on rlp_default_default rlp_5
+         Filter: (a >= 29)
+(11 rows)
+
+explain (costs off) select * from rlp where a < 1 or (a > 20 and a < 25);
+                      QUERY PLAN                      
+------------------------------------------------------
+ Append
+   ->  Seq Scan on rlp1 rlp_1
+         Filter: ((a < 1) OR ((a > 20) AND (a < 25)))
+   ->  Seq Scan on rlp4_1 rlp_2
+         Filter: ((a < 1) OR ((a > 20) AND (a < 25)))
+(5 rows)
+
+explain (costs off) select * from rlp where a = 20 or a = 40;
+                    QUERY PLAN                    
+--------------------------------------------------
+ Append
+   Subplans Removed: 2
+   ->  Seq Scan on rlp4_1 rlp_1
+         Filter: (a = ANY ('{20,40}'::integer[]))
+   ->  Seq Scan on rlp5_default rlp_2
+         Filter: (a = ANY ('{20,40}'::integer[]))
+(6 rows)
+
+explain (costs off) select * from rlp3 where a = 20;   /* empty */
+        QUERY PLAN        
+--------------------------
+ Result
+   One-Time Filter: false
+(2 rows)
+
+explain (costs off) select * from rlp where a > 1 and a = 10;	/* only default */
+            QUERY PLAN            
+----------------------------------
+ Seq Scan on rlp_default_10 rlp
+   Filter: ((a > 1) AND (a = 10))
+(2 rows)
+
+explain (costs off) select * from rlp where a > 1 and a >=15;	/* rlp3 onwards, including default */
+                  QUERY PLAN                  
+----------------------------------------------
+ Append
+   ->  Seq Scan on rlp3abcd rlp_1
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp3efgh rlp_2
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp3nullxy rlp_3
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp3_default rlp_4
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp4_1 rlp_5
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp4_2 rlp_6
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp4_default rlp_7
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp5_1 rlp_8
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp5_default rlp_9
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp_default_30 rlp_10
+         Filter: ((a > 1) AND (a >= 15))
+   ->  Seq Scan on rlp_default_default rlp_11
+         Filter: ((a > 1) AND (a >= 15))
+(23 rows)
+
+explain (costs off) select * from rlp where a = 1 and a = 3;	/* empty */
+        QUERY PLAN        
+--------------------------
+ Result
+   One-Time Filter: false
+(2 rows)
+
+explain (costs off) select * from rlp where (a = 1 and a = 3) or (a > 1 and a = 15);
+                            QUERY PLAN                             
+-------------------------------------------------------------------
+ Append
+   ->  Seq Scan on rlp2 rlp_1
+         Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
+   ->  Seq Scan on rlp3abcd rlp_2
+         Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
+   ->  Seq Scan on rlp3efgh rlp_3
+         Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
+   ->  Seq Scan on rlp3nullxy rlp_4
+         Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
+   ->  Seq Scan on rlp3_default rlp_5
+         Filter: (((a = 1) AND (a = 3)) OR ((a > 1) AND (a = 15)))
+(11 rows)
+
+RESET or_transform_limit;
 -- multi-column keys
 create table mc3p (a int, b int, c int) partition by range (a, abs(b), c);
 create table mc3p_default partition of mc3p default;
diff --git a/src/test/regress/expected/tidscan.out b/src/test/regress/expected/tidscan.out
index f133b5a4ac7..e462212aa54 100644
--- a/src/test/regress/expected/tidscan.out
+++ b/src/test/regress/expected/tidscan.out
@@ -56,6 +56,23 @@ SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
  (0,2) |  2
 (2 rows)
 
+SET or_transform_limit = 0;
+EXPLAIN (COSTS OFF)
+SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
+                          QUERY PLAN                          
+--------------------------------------------------------------
+ Tid Scan on tidscan
+   TID Cond: (ctid = ANY (ARRAY['(0,2)'::tid, '(0,1)'::tid]))
+(2 rows)
+
+SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
+ ctid  | id 
+-------+----
+ (0,1) |  1
+ (0,2) |  2
+(2 rows)
+
+RESET or_transform_limit;
 -- ctid = ScalarArrayOp - implemented as tidscan
 EXPLAIN (COSTS OFF)
 SELECT ctid, * FROM tidscan WHERE ctid = ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index d49ce9f3007..514e4f0da48 100644
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -737,6 +737,44 @@ SELECT count(*) FROM tenk1
 SELECT count(*) FROM tenk1
   WHERE hundred = 42 AND (thousand = 42 OR thousand = 99);
 
+SET or_transform_limit = 0;
+EXPLAIN (COSTS OFF)
+SELECT * FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3 OR tenthous = 42);
+SELECT * FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3 OR tenthous = 42);
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99);
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99);
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3) OR thousand = 41;
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 AND (tenthous = 1 OR tenthous = 3) OR thousand = 41;
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 OR tenthous = 1 AND thousand = 42 OR tenthous = 1;
+SELECT count(*) FROM tenk1
+  WHERE thousand = 42 OR tenthous = 1 AND thousand = 42 OR tenthous = 1;
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99 OR tenthous < 2) OR thousand = 41;
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 99 OR tenthous < 2) OR thousand = 41;
+
+EXPLAIN (COSTS OFF)
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 41 OR thousand = 99 AND tenthous = 2);
+SELECT count(*) FROM tenk1
+  WHERE hundred = 42 AND (thousand = 42 OR thousand = 41 OR thousand = 99 AND tenthous = 2);
+RESET or_transform_limit;
+
 --
 -- Check behavior with duplicate index column contents
 --
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index 3e5032b04dd..272ff7c5d90 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -1397,6 +1397,17 @@ select * from tenk1 a join tenk1 b on
   (a.unique1 = 1 and b.unique1 = 2) or
   ((a.unique2 = 3 or a.unique2 = 7) and b.hundred = 4);
 
+SET or_transform_limit = 0;
+explain (costs off)
+select * from tenk1 a join tenk1 b on
+  (a.unique1 = 1 and b.unique1 = 2) or
+  ((a.unique2 = 3 or a.unique2 = 7) and b.hundred = 4);
+explain (costs off)
+select * from tenk1 a join tenk1 b on
+  (a.unique1 < 20 or a.unique1 = 3 or a.unique1 = 1 and b.unique1 = 2) or
+  ((a.unique2 = 3 or a.unique2 = 7) and b.hundred = 4);
+RESET or_transform_limit;
+
 --
 -- test placement of movable quals in a parameterized join tree
 --
diff --git a/src/test/regress/sql/partition_prune.sql b/src/test/regress/sql/partition_prune.sql
index 83fed54b8c6..068eed3499c 100644
--- a/src/test/regress/sql/partition_prune.sql
+++ b/src/test/regress/sql/partition_prune.sql
@@ -21,6 +21,12 @@ explain (costs off) select * from lp where a is not null;
 explain (costs off) select * from lp where a is null;
 explain (costs off) select * from lp where a = 'a' or a = 'c';
 explain (costs off) select * from lp where a is not null and (a = 'a' or a = 'c');
+
+SET or_transform_limit = 0;
+explain (costs off) select * from lp where a = 'a' or a = 'c';
+explain (costs off) select * from lp where a is not null and (a = 'a' or a = 'c');
+RESET or_transform_limit;
+
 explain (costs off) select * from lp where a <> 'g';
 explain (costs off) select * from lp where a <> 'a' and a <> 'd';
 explain (costs off) select * from lp where a not in ('a', 'd');
@@ -99,6 +105,21 @@ explain (costs off) select * from rlp where a > 1 and a >=15;	/* rlp3 onwards, i
 explain (costs off) select * from rlp where a = 1 and a = 3;	/* empty */
 explain (costs off) select * from rlp where (a = 1 and a = 3) or (a > 1 and a = 15);
 
+SET or_transform_limit = 0;
+explain (costs off) select * from rlp where a = 1 or a = 7;
+explain (costs off) select * from rlp where a = 1 or b = 'ab';
+explain (costs off) select * from rlp where a > 20 and a < 27;
+explain (costs off) select * from rlp where a = 29;
+explain (costs off) select * from rlp where a >= 29;
+explain (costs off) select * from rlp where a < 1 or (a > 20 and a < 25);
+explain (costs off) select * from rlp where a = 20 or a = 40;
+explain (costs off) select * from rlp3 where a = 20;   /* empty */
+explain (costs off) select * from rlp where a > 1 and a = 10;	/* only default */
+explain (costs off) select * from rlp where a > 1 and a >=15;	/* rlp3 onwards, including default */
+explain (costs off) select * from rlp where a = 1 and a = 3;	/* empty */
+explain (costs off) select * from rlp where (a = 1 and a = 3) or (a > 1 and a = 15);
+RESET or_transform_limit;
+
 -- multi-column keys
 create table mc3p (a int, b int, c int) partition by range (a, abs(b), c);
 create table mc3p_default partition of mc3p default;
diff --git a/src/test/regress/sql/tidscan.sql b/src/test/regress/sql/tidscan.sql
index 313e0fb9b67..634bf08e5fc 100644
--- a/src/test/regress/sql/tidscan.sql
+++ b/src/test/regress/sql/tidscan.sql
@@ -22,6 +22,12 @@ EXPLAIN (COSTS OFF)
 SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
 SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
 
+SET or_transform_limit = 0;
+EXPLAIN (COSTS OFF)
+SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
+SELECT ctid, * FROM tidscan WHERE ctid = '(0,2)' OR '(0,1)' = ctid;
+RESET or_transform_limit;
+
 -- ctid = ScalarArrayOp - implemented as tidscan
 EXPLAIN (COSTS OFF)
 SELECT ctid, * FROM tidscan WHERE ctid = ANY(ARRAY['(0,1)', '(0,2)']::tid[]);
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 8de90c49585..b40b58124b4 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -1635,6 +1635,7 @@ NumericVar
 OM_uint32
 OP
 OSAPerGroupState
+OrClauseGroupEntry
 OSAPerQueryState
 OSInfo
 OSSLCipher