2 files changed, 365 insertions, 0 deletions
diff --git a/src/test/regress/expected/indexing.out b/src/test/regress/expected/indexing.out
index fb32ffffdc9..ecd2b110ff4 100644
--- a/src/test/regress/expected/indexing.out
+++ b/src/test/regress/expected/indexing.out
@@ -1067,6 +1067,255 @@ select tableoid::regclass, * from idxpart order by a;
 (8 rows)
 
 drop table idxpart;
+-- test fastpath mechanism for index insertion
+create table fastpath (a int, b text, c numeric);
+create unique index fpindex1 on fastpath(a);
+insert into fastpath values (1, 'b1', 100.00);
+insert into fastpath values (1, 'b1', 100.00); -- unique key check
+ERROR:  duplicate key value violates unique constraint "fpindex1"
+DETAIL:  Key (a)=(1) already exists.
+truncate fastpath;
+insert into fastpath select generate_series(1,10000), 'b', 100;
+-- vacuum the table so as to improve chances of index-only scans. we can't
+-- guarantee if index-only scans will be picked up in all cases or not, but
+-- that fuzziness actually helps the test.
+vacuum fastpath;
+set enable_seqscan to false;
+set enable_bitmapscan to false;
+explain select sum(a) from fastpath where a = 6456;
+                                     QUERY PLAN                                     
+------------------------------------------------------------------------------------
+ Aggregate  (cost=4.31..4.32 rows=1 width=8)
+   ->  Index Only Scan using fpindex1 on fastpath  (cost=0.29..4.30 rows=1 width=4)
+         Index Cond: (a = 6456)
+(3 rows)
+
+explain select sum(a) from fastpath where a >= 5000 and a < 5700;
+                                     QUERY PLAN                                      
+-------------------------------------------------------------------------------------
+ Aggregate  (cost=5.41..5.42 rows=1 width=8)
+   ->  Index Only Scan using fpindex1 on fastpath  (cost=0.29..5.29 rows=50 width=4)
+         Index Cond: ((a >= 5000) AND (a < 5700))
+(3 rows)
+
+select sum(a) from fastpath where a = 6456;
+ sum  
+------
+ 6456
+(1 row)
+
+select sum(a) from fastpath where a >= 5000 and a < 5700;
+   sum   
+---------
+ 3744650
+(1 row)
+
+-- drop the only index on the table and compute hashes for
+-- a few queries which orders the results in various different ways.
+drop index fpindex1;
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+-- now create a multi-column index with both column asc
+create index fpindex2 on fastpath(a, b);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+-- again, vacuum here either forces index-only scans or creates fuzziness
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+-- same queries with a different kind of index now. the final result must not
+-- change irrespective of what kind of index we have.
+drop index fpindex2;
+create index fpindex3 on fastpath(a desc, b asc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+-- repeat again
+drop index fpindex3;
+create index fpindex4 on fastpath(a asc, b desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+-- and again, this time indexing by (b, a). Note that column "b" has non-unique
+-- values.
+drop index fpindex4;
+create index fpindex5 on fastpath(b asc, a desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+-- one last time
+drop index fpindex5;
+create index fpindex6 on fastpath(b desc, a desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 6167a852b3e0679886b84a5405b5b53d
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ dfcf2bd5e5fea8397d47b2fd14618d31
+(1 row)
+
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+               md5                
+----------------------------------
+ 2ca216010a558a52d7df12f76dfc77ab
+(1 row)
+
+drop table fastpath;
 -- intentionally leave some objects around
 create table idxpart (a int) partition by range (a);
 create table idxpart1 partition of idxpart for values from (0) to (100);
diff --git a/src/test/regress/sql/indexing.sql b/src/test/regress/sql/indexing.sql
index c4ab89fc489..80f4adc6aad 100644
--- a/src/test/regress/sql/indexing.sql
+++ b/src/test/regress/sql/indexing.sql
@@ -574,6 +574,122 @@ insert into idxpart values (857142, 'six');
 select tableoid::regclass, * from idxpart order by a;
 drop table idxpart;
 
+-- test fastpath mechanism for index insertion
+create table fastpath (a int, b text, c numeric);
+create unique index fpindex1 on fastpath(a);
+
+insert into fastpath values (1, 'b1', 100.00);
+insert into fastpath values (1, 'b1', 100.00); -- unique key check
+
+truncate fastpath;
+insert into fastpath select generate_series(1,10000), 'b', 100;
+
+-- vacuum the table so as to improve chances of index-only scans. we can't
+-- guarantee if index-only scans will be picked up in all cases or not, but
+-- that fuzziness actually helps the test.
+vacuum fastpath;
+
+set enable_seqscan to false;
+set enable_bitmapscan to false;
+
+explain select sum(a) from fastpath where a = 6456;
+explain select sum(a) from fastpath where a >= 5000 and a < 5700;
+select sum(a) from fastpath where a = 6456;
+select sum(a) from fastpath where a >= 5000 and a < 5700;
+
+-- drop the only index on the table and compute hashes for
+-- a few queries which orders the results in various different ways.
+drop index fpindex1;
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+-- now create a multi-column index with both column asc
+create index fpindex2 on fastpath(a, b);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+-- again, vacuum here either forces index-only scans or creates fuzziness
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+-- same queries with a different kind of index now. the final result must not
+-- change irrespective of what kind of index we have.
+drop index fpindex2;
+create index fpindex3 on fastpath(a desc, b asc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+-- repeat again
+drop index fpindex3;
+create index fpindex4 on fastpath(a asc, b desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+-- and again, this time indexing by (b, a). Note that column "b" has non-unique
+-- values.
+drop index fpindex4;
+create index fpindex5 on fastpath(b asc, a desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+-- one last time
+drop index fpindex5;
+create index fpindex6 on fastpath(b desc, a desc);
+truncate fastpath;
+insert into fastpath select y.x, 'b' || (y.x/10)::text, 100 from (select generate_series(1,10000) as x) y;
+vacuum fastpath;
+select md5(string_agg(a::text, b order by a, b asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by a desc, b desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a desc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+select md5(string_agg(a::text, b order by b, a asc)) from fastpath
+	where a >= 1000 and a < 2000 and b > 'b1' and b < 'b3';
+
+drop table fastpath;
+
 -- intentionally leave some objects around
 create table idxpart (a int) partition by range (a);
 create table idxpart1 partition of idxpart for values from (0) to (100);