Updates the tests for the percentile functions

6 files changed, 298 insertions, 291 deletions

diff --git a/mysql-test/r/win_percentile.result b/mysql-test/r/win_percentile.result
index b365a995da0..c51e2e6bd51 100644
--- a/mysql-test/r/win_percentile.result
+++ b/mysql-test/r/win_percentile.result
@@ -4,58 +4,88 @@ INSERT INTO t1 VALUES
 ('Kaolin', 0.5, 3), ('Kaolin', 0.6, 7),
 ('Kaolin', 0.5, 4),
 ('Tatiana', 0.8, 4), ('Tata', 0.8, 4);
+#
+# Test invalid syntax
+#
+# Order by clause has more than one element
+select percentile_disc(0.5) within group(order by score,test) over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'test) over (partition by name) from t1' at line 1
+select percentile_cont(0.5) within group(order by score,test) over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'test) over (partition by name) from t1' at line 1
+# Order by clause has no element
+select percentile_disc(0.5) within group() over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ') over (partition by name) from t1' at line 1
+select percentile_cont(0.5) within group() over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ') over (partition by name) from t1' at line 1
+# No parameters to the percentile functions
+select percentile_disc() within group() over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ') within group() over (partition by name) from t1' at line 1
+select percentile_cont() within group() over (partition by name) from t1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ') within group() over (partition by name) from t1' at line 1
+#
+# Test simple syntax
+#
 select name, percentile_cont(0.5)  within group(order by score) over (partition by name) as c from t1;
 name	c
-Chun	5.00000
-Chun	5.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
-no partition clause
+Chun	5.0000000000
+Chun	5.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
+select name, percentile_disc(0.5)  within group(order by score) over (partition by name) as c from t1;
+name	c
+Chun	3.0000000000
+Chun	3.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
+# no partition clause
 select name, percentile_disc(0.5) within group(order by score)  over ()  from t1;
 name	percentile_disc(0.5) within group(order by score)  over ()
-Chun	4.00000
-Chun	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
+Chun	4.0000000000
+Chun	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
 select name, percentile_cont(0.5) within group(order by score)  over ()  from t1;
 name	percentile_cont(0.5) within group(order by score)  over ()
-Chun	4.00000
-Chun	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
-argument set to null
+Chun	4.0000000000
+Chun	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
+# argument set to null
 select name, percentile_cont(null)  within group(order by score) over (partition by name) from t1;
-ERROR HY000: Numeric values are only allowed as arguments to percentile functions
+ERROR HY000: percentile_cont function only accepts arguments that can be converted to numerical types
 select name, percentile_disc(null)  within group(order by score) over (partition by name) from t1;
-ERROR HY000: Numeric values are only allowed as arguments to percentile functions
-subqueries having percentile functions
+ERROR HY000: percentile_disc function only accepts arguments that can be converted to numerical types
+#subqueries having percentile functions
 select * from ( select name , percentile_cont(0.5) within group ( order by score) over (partition by name ) from t1 ) as t;
 name	percentile_cont(0.5) within group ( order by score) over (partition by name )
-Chun	5.00000
-Chun	5.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
+Chun	5.0000000000
+Chun	5.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
 select * from ( select name , percentile_disc(0.5) within group ( order by score) over (partition by name ) from t1 ) as t;
 name	percentile_disc(0.5) within group ( order by score) over (partition by name )
-Chun	3.00000
-Chun	3.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
+Chun	3.0000000000
+Chun	3.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
 select name from t1 a where (select  percentile_disc(0.5) within group (order by score) over (partition by name) from t1 b limit 1) >= 0.5;
 name
 Chun
@@ -65,241 +95,232 @@ Kaolin
 Kaolin
 Tatiana
 Tata
-disallowed fields in order by
+#disallowed fields in order by
 select score,  percentile_cont(0.5)  within group(order by name) over (partition by score) from t1;
-ERROR HY000: Numeric datatype is required for Percentile_CONT function
+ERROR HY000: Numeric datatype is required for percentile_cont function
 select score,  percentile_disc(0.5)  within group(order by name) over (partition by score) from t1;
-score	percentile_disc(0.5)  within group(order by name) over (partition by score)
-3.0000	Chun
-7.0000	Chun
-3.0000	Chun
-7.0000	Chun
-4.0000	Tata
-4.0000	Tata
-4.0000	Tata
-order by clause has more than one element
-select percentile_disc(0.5) within group(order by score,test) over (partition by name) from t1;
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'test) over (partition by name) from t1' at line 1
-select percentile_cont(0.5) within group(order by score,test) over (partition by name) from t1;
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'test) over (partition by name) from t1' at line 1
-parameter value should be in the range of [0,1]
+ERROR HY000: Numeric datatype is required for percentile_disc function
+#parameter value should be in the range of [0,1]
 select percentile_disc(1.5) within group(order by score) over (partition by name) from t1;
-ERROR HY000: Argument to the percentile functions does not belong to the range [0,1]
+ERROR HY000: Argument to the percentile_disc function does not belong to the range [0,1]
 select percentile_cont(1.5) within group(order by score) over (partition by name) from t1;
-ERROR HY000: Argument to the percentile functions does not belong to the range [0,1]
+ERROR HY000: Argument to the percentile_cont function does not belong to the range [0,1]
+#Argument should remain constant for the entire partition
 select name,percentile_cont(test) within group(order by score) over (partition by name) from t1;
-ERROR HY000: Argument to the percentile functions is not a constant
+ERROR HY000: Argument to the percentile_cont function is not a constant for a partition
 select name, percentile_disc(test) within group(order by score) over (partition by name) from t1;
-ERROR HY000: Argument to the percentile functions is not a constant
-only numerical types are allowed as argument to percentile functions
+ERROR HY000: Argument to the percentile_disc function is not a constant for a partition
+#only numerical types are allowed as argument to percentile functions
 select name, percentile_cont(name) within group(order by score) over (partition by name) from t1;
-ERROR HY000: Numeric values are only allowed as arguments to percentile functions
-complete query with partition column
+ERROR HY000: percentile_cont function only accepts arguments that can be converted to numerical types
+select name, percentile_disc(name) within group(order by score) over (partition by name) from t1;
+ERROR HY000: percentile_disc function only accepts arguments that can be converted to numerical types
+#complete query with partition column
 select name,cume_dist() over (partition by name order by score), percentile_disc(0.5)  within group(order by score) over (partition by name) as c from t1;
 name	cume_dist() over (partition by name order by score)	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	4.00000
-Kaolin	1.0000000000	4.00000
-Kaolin	0.6666666667	4.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	4.0000000000
+Kaolin	1.0000000000	4.0000000000
+Kaolin	0.6666666667	4.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name, percentile_cont(0.5)  within group(order by score) over (partition by name) as c from t1;
 name	c
-Chun	5.00000
-Chun	5.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Kaolin	4.00000
-Tatiana	4.00000
-Tata	4.00000
+Chun	5.0000000000
+Chun	5.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Kaolin	4.0000000000
+Tatiana	4.0000000000
+Tata	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.1)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	3.00000
-Kaolin	1.0000000000	3.00000
-Kaolin	0.6666666667	3.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	3.0000000000
+Kaolin	1.0000000000	3.0000000000
+Kaolin	0.6666666667	3.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.2)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	3.00000
-Kaolin	1.0000000000	3.00000
-Kaolin	0.6666666667	3.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	3.0000000000
+Kaolin	1.0000000000	3.0000000000
+Kaolin	0.6666666667	3.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.3)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	3.00000
-Kaolin	1.0000000000	3.00000
-Kaolin	0.6666666667	3.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	3.0000000000
+Kaolin	1.0000000000	3.0000000000
+Kaolin	0.6666666667	3.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.4)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	4.00000
-Kaolin	1.0000000000	4.00000
-Kaolin	0.6666666667	4.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	4.0000000000
+Kaolin	1.0000000000	4.0000000000
+Kaolin	0.6666666667	4.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.5)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	3.00000
-Chun	1.0000000000	3.00000
-Kaolin	0.3333333333	4.00000
-Kaolin	1.0000000000	4.00000
-Kaolin	0.6666666667	4.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	3.0000000000
+Chun	1.0000000000	3.0000000000
+Kaolin	0.3333333333	4.0000000000
+Kaolin	1.0000000000	4.0000000000
+Kaolin	0.6666666667	4.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.6)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	7.00000
-Chun	1.0000000000	7.00000
-Kaolin	0.3333333333	4.00000
-Kaolin	1.0000000000	4.00000
-Kaolin	0.6666666667	4.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	7.0000000000
+Chun	1.0000000000	7.0000000000
+Kaolin	0.3333333333	4.0000000000
+Kaolin	1.0000000000	4.0000000000
+Kaolin	0.6666666667	4.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.7)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	7.00000
-Chun	1.0000000000	7.00000
-Kaolin	0.3333333333	7.00000
-Kaolin	1.0000000000	7.00000
-Kaolin	0.6666666667	7.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	7.0000000000
+Chun	1.0000000000	7.0000000000
+Kaolin	0.3333333333	7.0000000000
+Kaolin	1.0000000000	7.0000000000
+Kaolin	0.6666666667	7.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.8)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	7.00000
-Chun	1.0000000000	7.00000
-Kaolin	0.3333333333	7.00000
-Kaolin	1.0000000000	7.00000
-Kaolin	0.6666666667	7.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	7.0000000000
+Chun	1.0000000000	7.0000000000
+Kaolin	0.3333333333	7.0000000000
+Kaolin	1.0000000000	7.0000000000
+Kaolin	0.6666666667	7.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(0.9)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	7.00000
-Chun	1.0000000000	7.00000
-Kaolin	0.3333333333	7.00000
-Kaolin	1.0000000000	7.00000
-Kaolin	0.6666666667	7.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	7.0000000000
+Chun	1.0000000000	7.0000000000
+Kaolin	0.3333333333	7.0000000000
+Kaolin	1.0000000000	7.0000000000
+Kaolin	0.6666666667	7.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select name,cume_dist() over (partition by name order by score) as b, percentile_disc(1)  within group(order by score) over (partition by name) as c from t1;
 name	b	c
-Chun	0.5000000000	7.00000
-Chun	1.0000000000	7.00000
-Kaolin	0.3333333333	7.00000
-Kaolin	1.0000000000	7.00000
-Kaolin	0.6666666667	7.00000
-Tatiana	1.0000000000	4.00000
-Tata	1.0000000000	4.00000
+Chun	0.5000000000	7.0000000000
+Chun	1.0000000000	7.0000000000
+Kaolin	0.3333333333	7.0000000000
+Kaolin	1.0000000000	7.0000000000
+Kaolin	0.6666666667	7.0000000000
+Tatiana	1.0000000000	4.0000000000
+Tata	1.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	3.00000
-5.00000	3.00000
-4.00000	3.00000
-4.00000	3.00000
-4.00000	3.00000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	3.0000000000
+5.0000000000	3.0000000000
+4.0000000000	3.0000000000
+4.0000000000	3.0000000000
+4.0000000000	3.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.1)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	3.40000
-5.00000	3.40000
-4.00000	3.20000
-4.00000	3.20000
-4.00000	3.20000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	3.4000000000
+5.0000000000	3.4000000000
+4.0000000000	3.2000000000
+4.0000000000	3.2000000000
+4.0000000000	3.2000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.2)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	3.80000
-5.00000	3.80000
-4.00000	3.40000
-4.00000	3.40000
-4.00000	3.40000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	3.8000000000
+5.0000000000	3.8000000000
+4.0000000000	3.4000000000
+4.0000000000	3.4000000000
+4.0000000000	3.4000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.3)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	4.20000
-5.00000	4.20000
-4.00000	3.60000
-4.00000	3.60000
-4.00000	3.60000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	4.2000000000
+5.0000000000	4.2000000000
+4.0000000000	3.6000000000
+4.0000000000	3.6000000000
+4.0000000000	3.6000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.4)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	4.60000
-5.00000	4.60000
-4.00000	3.80000
-4.00000	3.80000
-4.00000	3.80000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	4.6000000000
+5.0000000000	4.6000000000
+4.0000000000	3.8000000000
+4.0000000000	3.8000000000
+4.0000000000	3.8000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.5)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	5.00000
-5.00000	5.00000
-4.00000	4.00000
-4.00000	4.00000
-4.00000	4.00000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	5.0000000000
+5.0000000000	5.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.6)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	5.40000
-5.00000	5.40000
-4.00000	4.60000
-4.00000	4.60000
-4.00000	4.60000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	5.4000000000
+5.0000000000	5.4000000000
+4.0000000000	4.6000000000
+4.0000000000	4.6000000000
+4.0000000000	4.6000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.7)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	5.80000
-5.00000	5.80000
-4.00000	5.20000
-4.00000	5.20000
-4.00000	5.20000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	5.8000000000
+5.0000000000	5.8000000000
+4.0000000000	5.2000000000
+4.0000000000	5.2000000000
+4.0000000000	5.2000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.8)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	6.20000
-5.00000	6.20000
-4.00000	5.80000
-4.00000	5.80000
-4.00000	5.80000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	6.2000000000
+5.0000000000	6.2000000000
+4.0000000000	5.8000000000
+4.0000000000	5.8000000000
+4.0000000000	5.8000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(0.9)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	6.60000
-5.00000	6.60000
-4.00000	6.40000
-4.00000	6.40000
-4.00000	6.40000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	6.6000000000
+5.0000000000	6.6000000000
+4.0000000000	6.4000000000
+4.0000000000	6.4000000000
+4.0000000000	6.4000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 select median(score) over (partition by name), percentile_cont(1)  within group(order by score) over (partition by name) as c from t1;
 median(score) over (partition by name)	c
-5.00000	7.00000
-5.00000	7.00000
-4.00000	7.00000
-4.00000	7.00000
-4.00000	7.00000
-4.00000	4.00000
-4.00000	4.00000
+5.0000000000	7.0000000000
+5.0000000000	7.0000000000
+4.0000000000	7.0000000000
+4.0000000000	7.0000000000
+4.0000000000	7.0000000000
+4.0000000000	4.0000000000
+4.0000000000	4.0000000000
 drop table t1;
diff --git a/mysql-test/t/percentile.test b/mysql-test/t/percentile.test
deleted file mode 100644
index 0958fc05e7d..00000000000
--- a/mysql-test/t/percentile.test
+++ /dev/null
@@ -1,41 +0,0 @@
-CREATE TABLE student (name CHAR(10), test double, score TINYINT); 
-
-INSERT INTO student VALUES 
-('Chun', 0, null), ('Chun', 0, 4), 
-('Esben', 1, null), ('Esben', 1, null), 
-('Kaolin', 0.5, 56), ('Kaolin', 0.5, 88), 
-('Tatiana', 0.8, 2), ('Tatiana', 0.8, 1);
-
-
-
-select name, percentile_disc(0.6)  within group(order by score) over (partition by name) from student;
-select name, percentile_disc(test)  within group(order by score) over (partition by name) from student;
-select name, percentile_disc(0.4)  within group(order by score) over (partition by name) from student;
-
-
-#select name, percentile_cont(null)  within group(order by score) over (partition by name) from student;
-#select name, cume_dist()  over (partition by name order by score) from student;
-
-
-#normal parsing
-#select percentile_cont(0.5) within group(order by score)  over w1  from student
-#window w1 AS (partition by name);
-
-# no partition clause
-#select percentile_cont(0.5) within group(order by score)  over ()  from student;
-
-
-# only one sort allowed
-#select percentile_cont(0.5) within group(order by score) over (partition by name);
-
-#parameter value should be in the range of 0 to 1
-#select percentile_cont(1.5) within group(order by score) over (partition by name);
-
-
-#
-#select rank() over (partition by name order by score  ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) from student;
-
-
-
-drop table student;
-
diff --git a/mysql-test/t/win_percentile.test b/mysql-test/t/win_percentile.test
index cab3478241c..468d8cff56b 100644
--- a/mysql-test/t/win_percentile.test
+++ b/mysql-test/t/win_percentile.test
@@ -5,50 +5,77 @@ INSERT INTO t1 VALUES
 ('Kaolin', 0.5, 4),
 ('Tatiana', 0.8, 4), ('Tata', 0.8, 4);
 
+--echo #
+--echo # Test invalid syntax
+--echo #
+
+--echo # Order by clause has more than one element
+--error ER_PARSE_ERROR
+select percentile_disc(0.5) within group(order by score,test) over (partition by name) from t1;
+--error ER_PARSE_ERROR
+select percentile_cont(0.5) within group(order by score,test) over (partition by name) from t1;
+
+--echo # Order by clause has no element
+--error ER_PARSE_ERROR
+select percentile_disc(0.5) within group() over (partition by name) from t1;
+--error ER_PARSE_ERROR
+select percentile_cont(0.5) within group() over (partition by name) from t1;
+
+--echo # No parameters to the percentile functions
+--error ER_PARSE_ERROR
+select percentile_disc() within group() over (partition by name) from t1;
+--error ER_PARSE_ERROR
+select percentile_cont() within group() over (partition by name) from t1;
+
+
+
+--echo #
+--echo # Test simple syntax
+--echo #
+
 select name, percentile_cont(0.5)  within group(order by score) over (partition by name) as c from t1;
+select name, percentile_disc(0.5)  within group(order by score) over (partition by name) as c from t1;
 
---echo no partition clause
+--echo # no partition clause
 select name, percentile_disc(0.5) within group(order by score)  over ()  from t1;
 select name, percentile_cont(0.5) within group(order by score)  over ()  from t1;
 
---echo argument set to null
+--echo # argument set to null
 --error ER_WRONG_TYPE_OF_ARGUMENT
 select name, percentile_cont(null)  within group(order by score) over (partition by name) from t1;
 --error ER_WRONG_TYPE_OF_ARGUMENT
 select name, percentile_disc(null)  within group(order by score) over (partition by name) from t1;
 
---echo subqueries having percentile functions
+--echo #subqueries having percentile functions
 select * from ( select name , percentile_cont(0.5) within group ( order by score) over (partition by name ) from t1 ) as t;
 select * from ( select name , percentile_disc(0.5) within group ( order by score) over (partition by name ) from t1 ) as t;
 select name from t1 a where (select  percentile_disc(0.5) within group (order by score) over (partition by name) from t1 b limit 1) >= 0.5;
 
---echo disallowed fields in order by
---error ER_WRONG_TYPE_FOR_PERCENTILE_CONT
+--echo #disallowed fields in order by
+--error ER_WRONG_TYPE_FOR_PERCENTILE_FUNC
 select score,  percentile_cont(0.5)  within group(order by name) over (partition by score) from t1;
+--error ER_WRONG_TYPE_FOR_PERCENTILE_FUNC
 select score,  percentile_disc(0.5)  within group(order by name) over (partition by score) from t1;
 
---echo order by clause has more than one element
---error ER_PARSE_ERROR
-select percentile_disc(0.5) within group(order by score,test) over (partition by name) from t1;
---error ER_PARSE_ERROR
-select percentile_cont(0.5) within group(order by score,test) over (partition by name) from t1;
-
---echo parameter value should be in the range of [0,1]
+--echo #parameter value should be in the range of [0,1]
 --error ER_ARGUMENT_OUT_OF_RANGE
 select percentile_disc(1.5) within group(order by score) over (partition by name) from t1;
 --error ER_ARGUMENT_OUT_OF_RANGE
 select percentile_cont(1.5) within group(order by score) over (partition by name) from t1;
 
+--echo #Argument should remain constant for the entire partition
 --error ER_ARGUMENT_NOT_CONSTANT
 select name,percentile_cont(test) within group(order by score) over (partition by name) from t1;
 --error ER_ARGUMENT_NOT_CONSTANT
 select name, percentile_disc(test) within group(order by score) over (partition by name) from t1;
 
---echo only numerical types are allowed as argument to percentile functions
+--echo #only numerical types are allowed as argument to percentile functions
 --error ER_WRONG_TYPE_OF_ARGUMENT
 select name, percentile_cont(name) within group(order by score) over (partition by name) from t1;
+--error ER_WRONG_TYPE_OF_ARGUMENT
+select name, percentile_disc(name) within group(order by score) over (partition by name) from t1;
 
---echo complete query with partition column
+--echo #complete query with partition column
 select name,cume_dist() over (partition by name order by score), percentile_disc(0.5)  within group(order by score) over (partition by name) as c from t1;
 select name, percentile_cont(0.5)  within group(order by score) over (partition by name) as c from t1;
 
diff --git a/sql/item_windowfunc.cc b/sql/item_windowfunc.cc
index d38befa66bc..8432ab43ad8 100644
--- a/sql/item_windowfunc.cc
+++ b/sql/item_windowfunc.cc
@@ -174,11 +174,11 @@ bool Item_window_func::check_result_type_of_order_item()
   if (only_single_element_order_list())
   {
     Item_result rtype= window_spec->order_list->first->item[0]->cmp_type();
-    // TODO (varun) : support date type in percentile_cont function 
+    // TODO (varun) : support date type in percentile_cont function
     if (rtype != REAL_RESULT && rtype != INT_RESULT &&
         rtype != DECIMAL_RESULT && rtype != TIME_RESULT)
     {
-      my_error(ER_WRONG_TYPE_FOR_PERCENTILE_FUNC, MYF(0));
+      my_error(ER_WRONG_TYPE_FOR_PERCENTILE_FUNC, MYF(0), window_func()->func_name());
       return TRUE;
     }
     setting_handler_for_percentile_functions(rtype);
@@ -249,7 +249,7 @@ bool Item_sum_percentile_cont::fix_fields(THD *thd, Item **ref)
     case INT_RESULT:
       break;
     default:
-      my_error(ER_WRONG_TYPE_OF_ARGUMENT, MYF(0));
+      my_error(ER_WRONG_TYPE_OF_ARGUMENT, MYF(0), func_name());
       return TRUE;
   }
   return res;
@@ -268,7 +268,7 @@ bool Item_sum_percentile_disc::fix_fields(THD *thd, Item **ref)
     case INT_RESULT:
       break;
     default:
-      my_error(ER_WRONG_TYPE_OF_ARGUMENT, MYF(0));
+      my_error(ER_WRONG_TYPE_OF_ARGUMENT, MYF(0), func_name());
       return TRUE;
   }
   return res;
diff --git a/sql/item_windowfunc.h b/sql/item_windowfunc.h
index a3056dc222a..849c298f5aa 100644
--- a/sql/item_windowfunc.h
+++ b/sql/item_windowfunc.h
@@ -786,7 +786,7 @@ public:
     value->store(order_item);
     value->cache_value();
     if (value->null_value)
-       return false;
+      return false;
 
     Item_sum_cume_dist::add();
     double val= Item_sum_cume_dist::val_real();
@@ -821,7 +821,7 @@ public:
 
   void fix_length_and_dec()
   {
-    decimals = 5;  // TODO-cvicentiu find out how many decimals the standard
+    decimals = 10;  // TODO-cvicentiu find out how many decimals the standard
                     // requires.
   }
 
@@ -904,24 +904,24 @@ public:
       floor_value->store(order_item);
       floor_value->cache_value();
       if (floor_value->null_value)
-       return false;
+        return false;
     }
     if (floor_val_calculated && !ceil_val_calculated)
     {
       ceil_value->store(order_item);
       ceil_value->cache_value();
       if (ceil_value->null_value)
-       return false;
+        return false;
     }
 
     Item_sum_cume_dist::add();
     double val= 1 + prev_value * (get_row_count()-1);
 
     if (!floor_val_calculated && get_row_number() == floor(val))
-       floor_val_calculated= true;
+      floor_val_calculated= true;
 
     if (!ceil_val_calculated && get_row_number() == ceil(val))
-       ceil_val_calculated= true;
+      ceil_val_calculated= true;
     return false;
   }
 
@@ -951,7 +951,7 @@ public:
 
   void fix_length_and_dec()
   {
-    decimals = 5;  // TODO-cvicentiu find out how many decimals the standard
+    decimals = 10;  // TODO-cvicentiu find out how many decimals the standard
                     // requires.
   }
 
diff --git a/sql/sql_window.cc b/sql/sql_window.cc
index 059dd8073f5..4bcdca3ca11 100644
--- a/sql/sql_window.cc
+++ b/sql/sql_window.cc
@@ -1765,7 +1765,7 @@ protected:
   }
 };
 
-class Frame_unbounded_following_set_count_no_nulls: 
+class Frame_unbounded_following_set_count_no_nulls:
             public Frame_unbounded_following_set_count
 {