Extend the set of frame options supported for window functions.

This patch allows the frame to start from CURRENT ROW (in either RANGE or
ROWS mode), and it also adds support for ROWS n PRECEDING and ROWS n FOLLOWING
start and end points.  (RANGE value PRECEDING/FOLLOWING isn't there yet ---
the grammar works, but that's all.)

Hitoshi Harada, reviewed by Pavel Stehule

4 files changed, 245 insertions, 5 deletions

diff --git a/src/test/regress/expected/window.out b/src/test/regress/expected/window.out
index c14011ce0e4..0481cc6dd81 100644
--- a/src/test/regress/expected/window.out
+++ b/src/test/regress/expected/window.out
@@ -728,6 +728,193 @@ FROM (select distinct ten, four from tenk1) ss;
     3 |   2 |   4 |          2
 (20 rows)
 
+SELECT sum(unique1) over (order by four range between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+  45 |       0 |    0
+  45 |       8 |    0
+  45 |       4 |    0
+  33 |       5 |    1
+  33 |       9 |    1
+  33 |       1 |    1
+  18 |       6 |    2
+  18 |       2 |    2
+  10 |       3 |    3
+  10 |       7 |    3
+(10 rows)
+
+SELECT sum(unique1) over (rows between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+  45 |       4 |    0
+  41 |       2 |    2
+  39 |       1 |    1
+  38 |       6 |    2
+  32 |       9 |    1
+  23 |       8 |    0
+  15 |       5 |    1
+  10 |       3 |    3
+   7 |       7 |    3
+   0 |       0 |    0
+(10 rows)
+
+SELECT sum(unique1) over (rows between 2 preceding and 2 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+   7 |       4 |    0
+  13 |       2 |    2
+  22 |       1 |    1
+  26 |       6 |    2
+  29 |       9 |    1
+  31 |       8 |    0
+  32 |       5 |    1
+  23 |       3 |    3
+  15 |       7 |    3
+  10 |       0 |    0
+(10 rows)
+
+SELECT sum(unique1) over (rows between 2 preceding and 1 preceding),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+     |       4 |    0
+   4 |       2 |    2
+   6 |       1 |    1
+   3 |       6 |    2
+   7 |       9 |    1
+  15 |       8 |    0
+  17 |       5 |    1
+  13 |       3 |    3
+   8 |       7 |    3
+  10 |       0 |    0
+(10 rows)
+
+SELECT sum(unique1) over (rows between 1 following and 3 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+   9 |       4 |    0
+  16 |       2 |    2
+  23 |       1 |    1
+  22 |       6 |    2
+  16 |       9 |    1
+  15 |       8 |    0
+  10 |       5 |    1
+   7 |       3 |    3
+   0 |       7 |    3
+     |       0 |    0
+(10 rows)
+
+SELECT sum(unique1) over (rows between unbounded preceding and 1 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 | four 
+-----+---------+------
+   6 |       4 |    0
+   7 |       2 |    2
+  13 |       1 |    1
+  22 |       6 |    2
+  30 |       9 |    1
+  35 |       8 |    0
+  38 |       5 |    1
+  45 |       3 |    3
+  45 |       7 |    3
+  45 |       0 |    0
+(10 rows)
+
+SELECT sum(unique1) over (w range between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10 WINDOW w AS (order by four);
+ sum | unique1 | four 
+-----+---------+------
+  45 |       0 |    0
+  45 |       8 |    0
+  45 |       4 |    0
+  33 |       5 |    1
+  33 |       9 |    1
+  33 |       1 |    1
+  18 |       6 |    2
+  18 |       2 |    2
+  10 |       3 |    3
+  10 |       7 |    3
+(10 rows)
+
+-- fail: not implemented yet
+SELECT sum(unique1) over (order by four range between 2::int8 preceding and 1::int2 preceding),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+ERROR:  RANGE PRECEDING is only supported with UNBOUNDED
+LINE 1: SELECT sum(unique1) over (order by four range between 2::int...
+                                                ^
+SELECT first_value(unique1) over w,
+	nth_value(unique1, 2) over w AS nth_2,
+	last_value(unique1) over w, unique1, four
+FROM tenk1 WHERE unique1 < 10
+WINDOW w AS (order by four range between current row and unbounded following);
+ first_value | nth_2 | last_value | unique1 | four 
+-------------+-------+------------+---------+------
+           0 |     8 |          7 |       0 |    0
+           0 |     8 |          7 |       8 |    0
+           0 |     8 |          7 |       4 |    0
+           5 |     9 |          7 |       5 |    1
+           5 |     9 |          7 |       9 |    1
+           5 |     9 |          7 |       1 |    1
+           6 |     2 |          7 |       6 |    2
+           6 |     2 |          7 |       2 |    2
+           3 |     7 |          7 |       3 |    3
+           3 |     7 |          7 |       7 |    3
+(10 rows)
+
+SELECT sum(unique1) over
+	(rows (SELECT unique1 FROM tenk1 ORDER BY unique1 LIMIT 1) + 1 PRECEDING),
+	unique1
+FROM tenk1 WHERE unique1 < 10;
+ sum | unique1 
+-----+---------
+   4 |       4
+   6 |       2
+   3 |       1
+   7 |       6
+  15 |       9
+  17 |       8
+  13 |       5
+   8 |       3
+  10 |       7
+   7 |       0
+(10 rows)
+
+CREATE TEMP VIEW v_window AS
+	SELECT i, sum(i) over (order by i rows between 1 preceding and 1 following) as sum_rows
+	FROM generate_series(1, 10) i;
+SELECT * FROM v_window;
+ i  | sum_rows 
+----+----------
+  1 |        3
+  2 |        6
+  3 |        9
+  4 |       12
+  5 |       15
+  6 |       18
+  7 |       21
+  8 |       24
+  9 |       27
+ 10 |       19
+(10 rows)
+
+SELECT pg_get_viewdef('v_window');
+                                                         pg_get_viewdef                                                          
+---------------------------------------------------------------------------------------------------------------------------------
+ SELECT i.i, sum(i.i) OVER (ORDER BY i.i ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING) AS sum_rows FROM generate_series(1, 10) i(i);
+(1 row)
+
 -- with UNION
 SELECT count(*) OVER (PARTITION BY four) FROM (SELECT * FROM tenk1 UNION ALL SELECT * FROM tenk2)s LIMIT 0;
  count 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 43794122f56..7cdf872df59 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -1,5 +1,5 @@
 # ----------
-# $PostgreSQL: pgsql/src/test/regress/parallel_schedule,v 1.60 2010/02/07 22:40:33 tgl Exp $
+# $PostgreSQL: pgsql/src/test/regress/parallel_schedule,v 1.61 2010/02/12 17:33:21 tgl Exp $
 #
 # By convention, we put no more than twenty tests in any one parallel group;
 # this limits the number of connections needed to run the tests.
@@ -78,18 +78,19 @@ test: select_into select_distinct select_distinct_on select_implicit select_havi
 
 test: privileges
 test: misc
+# rules cannot run concurrently with any test that creates a view
+test: rules
 
 # ----------
 # Another group of parallel tests
 # ----------
-test: select_views portals_p2 rules foreign_key cluster dependency guc bitmapops combocid tsearch tsdicts foreign_data window xmlmap
+test: select_views portals_p2 foreign_key cluster dependency guc bitmapops combocid tsearch tsdicts foreign_data window xmlmap
 
 # ----------
 # Another group of parallel tests
 # NB: temp.sql does a reconnect which transiently uses 2 connections,
 # so keep this parallel group to at most 19 tests
 # ----------
-# "plpgsql" cannot run concurrently with "rules", nor can "plancache"
 test: plancache limit plpgsql copy2 temp domain rangefuncs prepare without_oid conversion truncate alter_table sequence polymorphism rowtypes returning largeobject with xml
 
 # run stats by itself because its delay may be insufficient under heavy load
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 037abf2341c..c404d54206b 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -1,4 +1,4 @@
-# $PostgreSQL: pgsql/src/test/regress/serial_schedule,v 1.55 2010/01/28 23:21:13 petere Exp $
+# $PostgreSQL: pgsql/src/test/regress/serial_schedule,v 1.56 2010/02/12 17:33:21 tgl Exp $
 # This should probably be in an order similar to parallel_schedule.
 test: tablespace
 test: boolean
@@ -89,9 +89,9 @@ test: namespace
 test: prepared_xacts
 test: privileges
 test: misc
+test: rules
 test: select_views
 test: portals_p2
-test: rules
 test: foreign_key
 test: cluster
 test: dependency
diff --git a/src/test/regress/sql/window.sql b/src/test/regress/sql/window.sql
index fc62a6fd6e9..1cfc64bd8b6 100644
--- a/src/test/regress/sql/window.sql
+++ b/src/test/regress/sql/window.sql
@@ -161,6 +161,58 @@ SELECT four, ten/4 as two,
 	last_value(ten/4) over (partition by four order by ten/4 rows between unbounded preceding and current row)
 FROM (select distinct ten, four from tenk1) ss;
 
+SELECT sum(unique1) over (order by four range between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (rows between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (rows between 2 preceding and 2 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (rows between 2 preceding and 1 preceding),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (rows between 1 following and 3 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (rows between unbounded preceding and 1 following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT sum(unique1) over (w range between current row and unbounded following),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10 WINDOW w AS (order by four);
+
+-- fail: not implemented yet
+SELECT sum(unique1) over (order by four range between 2::int8 preceding and 1::int2 preceding),
+	unique1, four
+FROM tenk1 WHERE unique1 < 10;
+
+SELECT first_value(unique1) over w,
+	nth_value(unique1, 2) over w AS nth_2,
+	last_value(unique1) over w, unique1, four
+FROM tenk1 WHERE unique1 < 10
+WINDOW w AS (order by four range between current row and unbounded following);
+
+SELECT sum(unique1) over
+	(rows (SELECT unique1 FROM tenk1 ORDER BY unique1 LIMIT 1) + 1 PRECEDING),
+	unique1
+FROM tenk1 WHERE unique1 < 10;
+
+CREATE TEMP VIEW v_window AS
+	SELECT i, sum(i) over (order by i rows between 1 preceding and 1 following) as sum_rows
+	FROM generate_series(1, 10) i;
+
+SELECT * FROM v_window;
+
+SELECT pg_get_viewdef('v_window');
+
 -- with UNION
 SELECT count(*) OVER (PARTITION BY four) FROM (SELECT * FROM tenk1 UNION ALL SELECT * FROM tenk2)s LIMIT 0;