fix: comments

Signed-off-by: Dennis Zhuang <[email protected]>

Author: killme2008

tests/cases/standalone/common/aggregate/approx_distinct.result

@@ -1,5 +1,5 @@
 -- Migrated from DuckDB test: test/sql/aggregate/aggregates/test_approximate_distinct_count.test
--- Test approx_count_distinct operator
+-- Test approx_distinct function
 -- Basic tests
 SELECT APPROX_DISTINCT(1);
 

tests/cases/standalone/common/aggregate/approx_distinct.sql

@@ -1,5 +1,5 @@
 -- Migrated from DuckDB test: test/sql/aggregate/aggregates/test_approximate_distinct_count.test
--- Test approx_count_distinct operator
+-- Test approx_distinct function
 
 -- Basic tests
 SELECT APPROX_DISTINCT(1);

tests/cases/standalone/common/aggregate/approx_percentile_cont.result

@@ -1,5 +1,5 @@
 -- Migrated from DuckDB test: test/sql/aggregate/aggregates/test_approx_quantile.test
--- Test APPROX_QUANTILE function
+-- Test approx_percentile_cont function instead of approx_quantile
 -- Test basic approximate quantile
 CREATE TABLE approx_test(i INTEGER, ts TIMESTAMP TIME INDEX);
 

tests/cases/standalone/common/aggregate/approx_percentile_cont.sql

@@ -1,5 +1,5 @@
 -- Migrated from DuckDB test: test/sql/aggregate/aggregates/test_approx_quantile.test
--- Test APPROX_QUANTILE function
+-- Test approx_percentile_cont function instead of approx_quantile
 
 -- Test basic approximate quantile
 CREATE TABLE approx_test(i INTEGER, ts TIMESTAMP TIME INDEX);

tests/cases/standalone/common/aggregate/avg.result

@@ -89,6 +89,7 @@ SELECT AVG(i), AVG(j) FROM vals;
 +-------------+-------------+
 
 -- FIXME(dennis): AVG(DISTINCT) not supported
+-- https://github.com/apache/datafusion/issues/2408
 -- SELECT AVG(DISTINCT i), AVG(DISTINCT j) FROM vals;
 -- cleanup
 DROP TABLE integers;

tests/cases/standalone/common/aggregate/avg.sql

@@ -37,6 +37,7 @@ INSERT INTO vals VALUES (1, 1.5, 1000), (2, 2.5, 2000), (3, 3.5, 3000), (NULL, N
 SELECT AVG(i), AVG(j) FROM vals;
 
 -- FIXME(dennis): AVG(DISTINCT) not supported
+-- https://github.com/apache/datafusion/issues/2408
 -- SELECT AVG(DISTINCT i), AVG(DISTINCT j) FROM vals;
 
 -- cleanup

tests/cases/standalone/common/aggregate/corr.result

@@ -9,7 +9,8 @@ SELECT corr(NULL,NULL);
 |                 |
 +-----------------+
 
--- Single value returns NaN
+-- Single value returns NULL
+-- FIXME(dennis): datafusion returns 0.0 here, should be NULL
 SELECT corr(1,1);
 
 +-------------------------+

tests/cases/standalone/common/aggregate/corr.sql

@@ -4,7 +4,8 @@
 -- Corner cases
 SELECT corr(NULL,NULL);
 
--- Single value returns NaN
+-- Single value returns NULL
+-- FIXME(dennis): datafusion returns 0.0 here, should be NULL
 SELECT corr(1,1);
 
 -- Test with table