[SPARK-28286][SQL][PYTHON][TESTS] Convert and port 'pivot.sql' into UDF test base

## What changes were proposed in this pull request?

This PR adds some tests converted from pivot.sql to test UDFs following the combination guide in [SPARK-27921](https://issues.apache.org/jira/browse/SPARK-27921).

<details><summary>Diff comparing to 'pivot.sql'</summary>
<p>

```diff
diff --git a/sql/core/src/test/resources/sql-tests/results/pivot.sql.out b/sql/core/src/test/resources/sql-tests/results/udf/udf-pivot.sql.out
index 9a8f783..cb9e4d7 100644
--- a/sql/core/src/test/resources/sql-tests/results/pivot.sql.out
+++ b/sql/core/src/test/resources/sql-tests/results/udf/udf-pivot.sql.out
 -1,5 +1,5
 -- Automatically generated by SQLQueryTestSuite
--- Number of queries: 32
+-- Number of queries: 30

 -- !query 0
 -40,14 +40,14  struct<>

 -- !query 3
 SELECT * FROM (
-  SELECT year, course, earnings FROM courseSales
+  SELECT udf(year), course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 3 schema
-struct<year:int,dotNET:bigint,Java:bigint>
+struct<CAST(udf(cast(year as string)) AS INT):int,dotNET:bigint,Java:bigint>
 -- !query 3 output
 2012   15000   20000
 2013   48000   30000
 -56,7 +56,7  struct<year:int,dotNET:bigint,Java:bigint>
 -- !query 4
 SELECT * FROM courseSales
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR year IN (2012, 2013)
 )
 -- !query 4 schema
 -71,11 +71,11  SELECT * FROM (
   SELECT year, course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings), avg(earnings)
+  udf(sum(earnings)), udf(avg(earnings))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 5 schema
-struct<year:int,dotNET_sum(CAST(earnings AS BIGINT)):bigint,dotNET_avg(CAST(earnings AS BIGINT)):double,Java_sum(CAST(earnings AS BIGINT)):bigint,Java_avg(CAST(earnings AS BIGINT)):double>
+struct<year:int,dotNET_CAST(udf(cast(sum(cast(earnings as bigint)) as string)) AS BIGINT):bigint,dotNET_CAST(udf(cast(avg(cast(earnings as bigint)) as string)) AS DOUBLE):double,Java_CAST(udf(cast(sum(cast(earnings as bigint)) as string)) AS BIGINT):bigint,Java_CAST(udf(cast(avg(cast(earnings as bigint)) as string)) AS DOUBLE):double>
 -- !query 5 output
 2012   15000   7500.0  20000   20000.0
 2013   48000   48000.0 30000   30000.0
 -83,10 +83,10  struct<year:int,dotNET_sum(CAST(earnings AS BIGINT)):bigint,dotNET_avg(CAST(earn

 -- !query 6
 SELECT * FROM (
-  SELECT course, earnings FROM courseSales
+  SELECT udf(course) as course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 6 schema
 -100,23 +100,23  SELECT * FROM (
   SELECT year, course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings), min(year)
+  udf(sum(udf(earnings))), udf(min(year))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 7 schema
-struct<dotNET_sum(CAST(earnings AS BIGINT)):bigint,dotNET_min(year):int,Java_sum(CAST(earnings AS BIGINT)):bigint,Java_min(year):int>
+struct<dotNET_CAST(udf(cast(sum(cast(cast(udf(cast(earnings as string)) as int) as bigint)) as string)) AS BIGINT):bigint,dotNET_CAST(udf(cast(min(year) as string)) AS INT):int,Java_CAST(udf(cast(sum(cast(cast(udf(cast(earnings as string)) as int) as bigint)) as string)) AS BIGINT):bigint,Java_CAST(udf(cast(min(year) as string)) AS INT):int>
 -- !query 7 output
 63000  2012    50000   2012

 -- !query 8
 SELECT * FROM (
-  SELECT course, year, earnings, s
+  SELECT course, year, earnings, udf(s) as s
   FROM courseSales
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR s IN (1, 2)
 )
 -- !query 8 schema
 -135,11 +135,11  SELECT * FROM (
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings), min(s)
+  udf(sum(earnings)), udf(min(s))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 9 schema
-struct<year:int,dotNET_sum(CAST(earnings AS BIGINT)):bigint,dotNET_min(s):int,Java_sum(CAST(earnings AS BIGINT)):bigint,Java_min(s):int>
+struct<year:int,dotNET_CAST(udf(cast(sum(cast(earnings as bigint)) as string)) AS BIGINT):bigint,dotNET_CAST(udf(cast(min(s) as string)) AS INT):int,Java_CAST(udf(cast(sum(cast(earnings as bigint)) as string)) AS BIGINT):bigint,Java_CAST(udf(cast(min(s) as string)) AS INT):int>
 -- !query 9 output
 2012   15000   1       20000   1
 2013   48000   2       30000   2
 -152,7 +152,7  SELECT * FROM (
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings * s)
+  udf(sum(earnings * s))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 10 schema
 -167,7 +167,7  SELECT 2012_s, 2013_s, 2012_a, 2013_a, c FROM (
   SELECT year y, course c, earnings e FROM courseSales
 )
 PIVOT (
-  sum(e) s, avg(e) a
+  udf(sum(e)) s, udf(avg(e)) a
   FOR y IN (2012, 2013)
 )
 -- !query 11 schema
 -182,7 +182,7  SELECT firstYear_s, secondYear_s, firstYear_a, secondYear_a, c FROM (
   SELECT year y, course c, earnings e FROM courseSales
 )
 PIVOT (
-  sum(e) s, avg(e) a
+  udf(sum(e)) s, udf(avg(e)) a
   FOR y IN (2012 as firstYear, 2013 secondYear)
 )
 -- !query 12 schema
 -195,7 +195,7  struct<firstYear_s:bigint,secondYear_s:bigint,firstYear_a:double,secondYear_a:do
 -- !query 13
 SELECT * FROM courseSales
 PIVOT (
-  abs(earnings)
+  udf(abs(earnings))
   FOR year IN (2012, 2013)
 )
 -- !query 13 schema
 -210,7 +210,7  SELECT * FROM (
   SELECT year, course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings), year
+  udf(sum(earnings)), year
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 14 schema
 -225,7 +225,7  SELECT * FROM (
   SELECT course, earnings FROM courseSales
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR year IN (2012, 2013)
 )
 -- !query 15 schema
 -240,11 +240,11  SELECT * FROM (
   SELECT year, course, earnings FROM courseSales
 )
 PIVOT (
-  ceil(sum(earnings)), avg(earnings) + 1 as a1
+  udf(ceil(udf(sum(earnings)))), avg(earnings) + 1 as a1
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 16 schema
-struct<year:int,dotNET_CEIL(sum(CAST(earnings AS BIGINT))):bigint,dotNET_a1:double,Java_CEIL(sum(CAST(earnings AS BIGINT))):bigint,Java_a1:double>
+struct<year:int,dotNET_CAST(udf(cast(CEIL(cast(udf(cast(sum(cast(earnings as bigint)) as string)) as bigint)) as string)) AS BIGINT):bigint,dotNET_a1:double,Java_CAST(udf(cast(CEIL(cast(udf(cast(sum(cast(earnings as bigint)) as string)) as bigint)) as string)) AS BIGINT):bigint,Java_a1:double>
 -- !query 16 output
 2012   15000   7501.0  20000   20001.0
 2013   48000   48001.0 30000   30001.0
 -255,7 +255,7  SELECT * FROM (
   SELECT year, course, earnings FROM courseSales
 )
 PIVOT (
-  sum(avg(earnings))
+  sum(udf(avg(earnings)))
   FOR course IN ('dotNET', 'Java')
 )
 -- !query 17 schema
 -272,7 +272,7  SELECT * FROM (
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, year) IN (('dotNET', 2012), ('Java', 2013))
 )
 -- !query 18 schema
 -289,7 +289,7  SELECT * FROM (
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, s) IN (('dotNET', 2) as c1, ('Java', 1) as c2)
 )
 -- !query 19 schema
 -306,7 +306,7  SELECT * FROM (
   JOIN years ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, year) IN ('dotNET', 'Java')
 )
 -- !query 20 schema
 -319,7 +319,7  Invalid pivot value 'dotNET': value data type string does not match pivot column
 -- !query 21
 SELECT * FROM courseSales
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR year IN (s, 2013)
 )
 -- !query 21 schema
 -332,7 +332,7  cannot resolve '`s`' given input columns: [coursesales.course, coursesales.earni
 -- !query 22
 SELECT * FROM courseSales
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR year IN (course, 2013)
 )
 -- !query 22 schema
 -343,151 +343,118  Literal expressions required for pivot values, found 'course#x';

 -- !query 23
-SELECT * FROM (
-  SELECT course, year, a
-  FROM courseSales
-  JOIN yearsWithComplexTypes ON year = y
-)
-PIVOT (
-  min(a)
-  FOR course IN ('dotNET', 'Java')
-)
--- !query 23 schema
-struct<year:int,dotNET:array<int>,Java:array<int>>
--- !query 23 output
-2012   [1,1]   [1,1]
-2013   [2,2]   [2,2]
-
-
--- !query 24
-SELECT * FROM (
-  SELECT course, year, y, a
-  FROM courseSales
-  JOIN yearsWithComplexTypes ON year = y
-)
-PIVOT (
-  max(a)
-  FOR (y, course) IN ((2012, 'dotNET'), (2013, 'Java'))
-)
--- !query 24 schema
-struct<year:int,[2012, dotNET]:array<int>,[2013, Java]:array<int>>
--- !query 24 output
-2012   [1,1]   NULL
-2013   NULL    [2,2]
-
-
--- !query 25
 SELECT * FROM (
   SELECT earnings, year, a
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR a IN (array(1, 1), array(2, 2))
 )
--- !query 25 schema
+-- !query 23 schema
 struct<year:int,[1, 1]:bigint,[2, 2]:bigint>
--- !query 25 output
+-- !query 23 output
 2012   35000   NULL
 2013   NULL    78000

--- !query 26
+-- !query 24
 SELECT * FROM (
-  SELECT course, earnings, year, a
+  SELECT course, earnings, udf(year) as year, a
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, a) IN (('dotNET', array(1, 1)), ('Java', array(2, 2)))
 )
--- !query 26 schema
+-- !query 24 schema
 struct<year:int,[dotNET, [1, 1]]:bigint,[Java, [2, 2]]:bigint>
--- !query 26 output
+-- !query 24 output
 2012   15000   NULL
 2013   NULL    30000

--- !query 27
+-- !query 25
 SELECT * FROM (
   SELECT earnings, year, s
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR s IN ((1, 'a'), (2, 'b'))
 )
--- !query 27 schema
+-- !query 25 schema
 struct<year:int,[1, a]:bigint,[2, b]:bigint>
--- !query 27 output
+-- !query 25 output
 2012   35000   NULL
 2013   NULL    78000

--- !query 28
+-- !query 26
 SELECT * FROM (
   SELECT course, earnings, year, s
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, s) IN (('dotNET', (1, 'a')), ('Java', (2, 'b')))
 )
--- !query 28 schema
+-- !query 26 schema
 struct<year:int,[dotNET, [1, a]]:bigint,[Java, [2, b]]:bigint>
--- !query 28 output
+-- !query 26 output
 2012   15000   NULL
 2013   NULL    30000

--- !query 29
+-- !query 27
 SELECT * FROM (
   SELECT earnings, year, m
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR m IN (map('1', 1), map('2', 2))
 )
--- !query 29 schema
+-- !query 27 schema
 struct<>
--- !query 29 output
+-- !query 27 output
 org.apache.spark.sql.AnalysisException
 Invalid pivot column 'm#x'. Pivot columns must be comparable.;

--- !query 30
+-- !query 28
 SELECT * FROM (
   SELECT course, earnings, year, m
   FROM courseSales
   JOIN yearsWithComplexTypes ON year = y
 )
 PIVOT (
-  sum(earnings)
+  udf(sum(earnings))
   FOR (course, m) IN (('dotNET', map('1', 1)), ('Java', map('2', 2)))
 )
--- !query 30 schema
+-- !query 28 schema
 struct<>
--- !query 30 output
+-- !query 28 output
 org.apache.spark.sql.AnalysisException
 Invalid pivot column 'named_struct(course, course#x, m, m#x)'. Pivot columns must be comparable.;

--- !query 31
+-- !query 29
 SELECT * FROM (
-  SELECT course, earnings, "a" as a, "z" as z, "b" as b, "y" as y, "c" as c, "x" as x, "d" as d, "w" as w
+  SELECT course, earnings, udf("a") as a, udf("z") as z, udf("b") as b, udf("y") as y,
+  udf("c") as c, udf("x") as x, udf("d") as d, udf("w") as w
   FROM courseSales
 )
 PIVOT (
-  sum(Earnings)
+  udf(sum(Earnings))
   FOR Course IN ('dotNET', 'Java')
 )
--- !query 31 schema
+-- !query 29 schema
 struct<a:string,z:string,b:string,y:string,c:string,x:string,d:string,w:string,dotNET:bigint,Java:bigint>
--- !query 31 output
+-- !query 29 output
 a      z       b       y       c       x       d       w       63000   50000

```

</p>
</details>

## How was this patch tested?

Tested as guided in [SPARK-27921](https://issues.apache.org/jira/browse/SPARK-27921).

Closes apache#25122 from chitralverma/SPARK-28286.

Authored-by: chitralverma <[email protected]>
Signed-off-by: HyukjinKwon <[email protected]>

Author: chitralverma

sql/core/src/test/resources/sql-tests/inputs/udf/udf-pivot.sql

@@ -0,0 +1,307 @@
+-- This test file was converted from pivot.sql.
+
+-- Note some test cases have been commented as the current integrated UDFs cannot handle complex types
+
+create temporary view courseSales as select * from values
+  ("dotNET", 2012, 10000),
+  ("Java", 2012, 20000),
+  ("dotNET", 2012, 5000),
+  ("dotNET", 2013, 48000),
+  ("Java", 2013, 30000)
+  as courseSales(course, year, earnings);
+
+create temporary view years as select * from values
+  (2012, 1),
+  (2013, 2)
+  as years(y, s);
+
+create temporary view yearsWithComplexTypes as select * from values
+  (2012, array(1, 1), map('1', 1), struct(1, 'a')),
+  (2013, array(2, 2), map('2', 2), struct(2, 'b'))
+  as yearsWithComplexTypes(y, a, m, s);
+
+-- pivot courses
+SELECT * FROM (
+  SELECT udf(year), course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot years with no subquery
+SELECT * FROM courseSales
+PIVOT (
+  udf(sum(earnings))
+  FOR year IN (2012, 2013)
+);
+
+-- pivot courses with multiple aggregations
+SELECT * FROM (
+  SELECT year, course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(earnings)), udf(avg(earnings))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot with no group by column
+SELECT * FROM (
+  SELECT udf(course) as course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot with no group by column and with multiple aggregations on different columns
+SELECT * FROM (
+  SELECT year, course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(udf(earnings))), udf(min(year))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot on join query with multiple group by columns
+SELECT * FROM (
+  SELECT course, year, earnings, udf(s) as s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR s IN (1, 2)
+);
+
+-- pivot on join query with multiple aggregations on different columns
+SELECT * FROM (
+  SELECT course, year, earnings, s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings)), udf(min(s))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot on join query with multiple columns in one aggregation
+SELECT * FROM (
+  SELECT course, year, earnings, s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings * s))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot with aliases and projection
+SELECT 2012_s, 2013_s, 2012_a, 2013_a, c FROM (
+  SELECT year y, course c, earnings e FROM courseSales
+)
+PIVOT (
+  udf(sum(e)) s, udf(avg(e)) a
+  FOR y IN (2012, 2013)
+);
+
+-- pivot with projection and value aliases
+SELECT firstYear_s, secondYear_s, firstYear_a, secondYear_a, c FROM (
+  SELECT year y, course c, earnings e FROM courseSales
+)
+PIVOT (
+  udf(sum(e)) s, udf(avg(e)) a
+  FOR y IN (2012 as firstYear, 2013 secondYear)
+);
+
+-- pivot years with non-aggregate function
+SELECT * FROM courseSales
+PIVOT (
+  udf(abs(earnings))
+  FOR year IN (2012, 2013)
+);
+
+-- pivot with one of the expressions as non-aggregate function
+SELECT * FROM (
+  SELECT year, course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(earnings)), year
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot with unresolvable columns
+SELECT * FROM (
+  SELECT course, earnings FROM courseSales
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR year IN (2012, 2013)
+);
+
+-- pivot with complex aggregate expressions
+SELECT * FROM (
+  SELECT year, course, earnings FROM courseSales
+)
+PIVOT (
+  udf(ceil(udf(sum(earnings)))), avg(earnings) + 1 as a1
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot with invalid arguments in aggregate expressions
+SELECT * FROM (
+  SELECT year, course, earnings FROM courseSales
+)
+PIVOT (
+  sum(udf(avg(earnings)))
+  FOR course IN ('dotNET', 'Java')
+);
+
+-- pivot on multiple pivot columns
+SELECT * FROM (
+  SELECT course, year, earnings, s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, year) IN (('dotNET', 2012), ('Java', 2013))
+);
+
+-- pivot on multiple pivot columns with aliased values
+SELECT * FROM (
+  SELECT course, year, earnings, s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, s) IN (('dotNET', 2) as c1, ('Java', 1) as c2)
+);
+
+-- pivot on multiple pivot columns with values of wrong data types
+SELECT * FROM (
+  SELECT course, year, earnings, s
+  FROM courseSales
+  JOIN years ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, year) IN ('dotNET', 'Java')
+);
+
+-- pivot with unresolvable values
+SELECT * FROM courseSales
+PIVOT (
+  udf(sum(earnings))
+  FOR year IN (s, 2013)
+);
+
+-- pivot with non-literal values
+SELECT * FROM courseSales
+PIVOT (
+  udf(sum(earnings))
+  FOR year IN (course, 2013)
+);
+
+-- Complex type is not supported in the current UDF. Skipped for now.
+-- pivot on join query with columns of complex data types
+-- SELECT * FROM (
+--  SELECT course, year, a
+--  FROM courseSales
+--  JOIN yearsWithComplexTypes ON year = y
+--)
+--PIVOT (
+--  udf(min(a))
+--  FOR course IN ('dotNET', 'Java')
+--);
+
+-- Complex type is not supported in the current UDF. Skipped for now.
+-- pivot on multiple pivot columns with agg columns of complex data types
+-- SELECT * FROM (
+--  SELECT course, year, y, a
+--  FROM courseSales
+--  JOIN yearsWithComplexTypes ON year = y
+--)
+--PIVOT (
+--  udf(max(a))
+--  FOR (y, course) IN ((2012, 'dotNET'), (2013, 'Java'))
+--);
+
+-- pivot on pivot column of array type
+SELECT * FROM (
+  SELECT earnings, year, a
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR a IN (array(1, 1), array(2, 2))
+);
+
+-- pivot on multiple pivot columns containing array type
+SELECT * FROM (
+  SELECT course, earnings, udf(year) as year, a
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, a) IN (('dotNET', array(1, 1)), ('Java', array(2, 2)))
+);
+
+-- pivot on pivot column of struct type
+SELECT * FROM (
+  SELECT earnings, year, s
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR s IN ((1, 'a'), (2, 'b'))
+);
+
+-- pivot on multiple pivot columns containing struct type
+SELECT * FROM (
+  SELECT course, earnings, year, s
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, s) IN (('dotNET', (1, 'a')), ('Java', (2, 'b')))
+);
+
+-- pivot on pivot column of map type
+SELECT * FROM (
+  SELECT earnings, year, m
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR m IN (map('1', 1), map('2', 2))
+);
+
+-- pivot on multiple pivot columns containing map type
+SELECT * FROM (
+  SELECT course, earnings, year, m
+  FROM courseSales
+  JOIN yearsWithComplexTypes ON year = y
+)
+PIVOT (
+  udf(sum(earnings))
+  FOR (course, m) IN (('dotNET', map('1', 1)), ('Java', map('2', 2)))
+);
+
+-- grouping columns output in the same order as input
+-- correctly handle pivot columns with different cases
+SELECT * FROM (
+  SELECT course, earnings, udf("a") as a, udf("z") as z, udf("b") as b, udf("y") as y,
+  udf("c") as c, udf("x") as x, udf("d") as d, udf("w") as w
+  FROM courseSales
+)
+PIVOT (
+  udf(sum(Earnings))
+  FOR Course IN ('dotNET', 'Java')
+);