Spark SQL----内置函数Aggregate Functions

Aggregate Functions
例子：
-- any
SELECT any(col) FROM VALUES (true), (false), (false) AS tab(col);
+--------+
|any(col)|
+--------+
|    true|
+--------+

SELECT any(col) FROM VALUES (NULL), (true), (false) AS tab(col);
+--------+
|any(col)|
+--------+
|    true|
+--------+

SELECT any(col) FROM VALUES (false), (false), (NULL) AS tab(col);
+--------+
|any(col)|
+--------+
|   false|
+--------+

-- any_value
SELECT any_value(col) FROM VALUES (10), (5), (20) AS tab(col);
+--------------+
|any_value(col)|
+--------------+
|            10|
+--------------+

SELECT any_value(col) FROM VALUES (NULL), (5), (20) AS tab(col);
+--------------+
|any_value(col)|
+--------------+
|          NULL|
+--------------+

SELECT any_value(col, true) FROM VALUES (NULL), (5), (20) AS tab(col);
+--------------+
|any_value(col)|
+--------------+
|             5|
+--------------+

-- approx_count_distinct
SELECT approx_count_distinct(col1) FROM VALUES (1), (1), (2), (2), (3) tab(col1);
+---------------------------+
|approx_count_distinct(col1)|
+---------------------------+
|                          3|
+---------------------------+

-- approx_percentile
SELECT approx_percentile(col, array(0.5, 0.4, 0.1), 100) FROM VALUES (0), (1), (2), (10) AS tab(col);
+-------------------------------------------------+
|approx_percentile(col, array(0.5, 0.4, 0.1), 100)|
+-------------------------------------------------+
|                                        [1, 1, 0]|
+-------------------------------------------------+

SELECT approx_percentile(col, 0.5, 100) FROM VALUES (0), (6), (7), (9), (10) AS tab(col);
+--------------------------------+
|approx_percentile(col, 0.5, 100)|
+--------------------------------+
|                               7|
+--------------------------------+

SELECT approx_percentile(col, 0.5, 100) FROM VALUES (INTERVAL '0' MONTH), (INTERVAL '1' MONTH), (INTERVAL '2' MONTH), (INTERVAL '10' MONTH) AS tab(col);
+--------------------------------+
|approx_percentile(col, 0.5, 100)|
+--------------------------------+
|              INTERVAL '1' MONTH|
+--------------------------------+

SELECT approx_percentile(col, array(0.5, 0.7), 100) FROM VALUES (INTERVAL '0' SECOND), (INTERVAL '1' SECOND), (INTERVAL '2' SECOND), (INTERVAL '10' SECOND) AS tab(col);
+--------------------------------------------+
|approx_percentile(col, array(0.5, 0.7), 100)|
+--------------------------------------------+
|                        [INTERVAL '01' SE...|
+--------------------------------------------+

-- array_agg
SELECT array_agg(col) FROM VALUES (1), (2), (1) AS tab(col);
+-----------------+
|collect_list(col)|
+-----------------+
|        [1, 2, 1]|
+-----------------+

-- avg
SELECT avg(col) FROM VALUES (1), (2), (3) AS tab(col);
+--------+
|avg(col)|
+--------+
|     2.0|
+--------+

SELECT avg(col) FROM VALUES (1), (2), (NULL) AS tab(col);
+--------+
|avg(col)|
+--------+
|     1.5|
+--------+

-- bit_and
SELECT bit_and(col) FROM VALUES (3), (5) AS tab(col);
+------------+
|bit_and(col)|
+------------+
|           1|
+------------+

-- bit_or
SELECT bit_or(col) FROM VALUES (3), (5) AS tab(col);
+-----------+
|bit_or(col)|
+-----------+
|          7|
+-----------+

-- bit_xor
SELECT bit_xor(col) FROM VALUES (3), (5) AS tab(col);
+------------+
|bit_xor(col)|
+------------+
|           6|
+------------+

-- bitmap_construct_agg
SELECT substring(hex(bitmap_construct_agg(bitmap_bit_position(col))), 0, 6) FROM VALUES (1), (2), (3) AS tab(col);
+--------------------------------------------------------------------+
|substring(hex(bitmap_construct_agg(bitmap_bit_position(col))), 0, 6)|
+--------------------------------------------------------------------+
|                                                              070000|
+--------------------------------------------------------------------+

SELECT substring(hex(bitmap_construct_agg(bitmap_bit_position(col))), 0, 6) FROM VALUES (1), (1), (1) AS tab(col);
+--------------------------------------------------------------------+
|substring(hex(bitmap_construct_agg(bitmap_bit_position(col))), 0, 6)|
+--------------------------------------------------------------------+
|                                                              010000|
+--------------------------------------------------------------------+

-- bitmap_or_agg
SELECT substring(hex(bitmap_or_agg(col)), 0, 6) FROM VALUES (X '10'), (X '20'), (X '40') AS tab(col);
+----------------------------------------+
|substring(hex(bitmap_or_agg(col)), 0, 6)|
+----------------------------------------+
|                                  700000|
+----------------------------------------+

SELECT substring(hex(bitmap_or_agg(col)), 0, 6) FROM VALUES (X '10'), (X '10'), (X '10') AS tab(col);
+----------------------------------------+
|substring(hex(bitmap_or_agg(col)), 0, 6)|
+----------------------------------------+
|                                  100000|
+----------------------------------------+

-- bool_and
SELECT bool_and(col) FROM VALUES (true), (true), (true) AS tab(col);
+-------------+
|bool_and(col)|
+-------------+
|         true|
+-------------+

SELECT bool_and(col) FROM VALUES (NULL), (true), (true) AS tab(col);
+-------------+
|bool_and(col)|
+-------------+
|         true|
+-------------+

SELECT bool_and(col) FROM VALUES (true), (false), (true) AS tab(col);
+-------------+
|bool_and(col)|
+-------------+
|        false|
+-------------+

-- bool_or
SELECT bool_or(col) FROM VALUES (true), (false), (false) AS tab(col);
+------------+
|bool_or(col)|
+------------+
|        true|
+------------+

SELECT bool_or(col) FROM VALUES (NULL), (true), (false) AS tab(col);
+------------+
|bool_or(col)|
+------------+
|        true|
+------------+

SELECT bool_or(col) FROM VALUES (false), (false), (NULL) AS tab(col);
+------------+
|bool_or(col)|
+------------+
|       false|
+------------+

-- collect_list
SELECT collect_list(col) FROM VALUES (1), (2), (1) AS tab(col);
+-----------------+
|collect_list(col)|
+-----------------+
|        [1, 2, 1]|
+-----------------+

-- collect_set
SELECT collect_set(col) FROM VALUES (1), (2), (1) AS tab(col);
+----------------+
|collect_set(col)|
+----------------+
|          [1, 2]|
+----------------+

-- corr
SELECT corr(c1, c2) FROM VALUES (3, 2), (3, 3), (6, 4) as tab(c1, c2);
+------------------+
|      corr(c1, c2)|
+------------------+
|0.8660254037844387|
+------------------+

-- count
SELECT count(*) FROM VALUES (NULL), (5), (5), (20) AS tab(col);
+--------+
|count(1)|
+--------+
|       4|
+--------+

SELECT count(col) FROM VALUES (NULL), (5), (5), (20) AS tab(col);
+----------+
|count(col)|
+----------+
|         3|
+----------+

SELECT count(DISTINCT col) FROM VALUES (NULL), (5), (5), (10) AS tab(col);
+-------------------+
|count(DISTINCT col)|
+-------------------+
|                  2|
+-------------------+

-- count_if
SELECT count_if(col % 2 = 0) FROM VALUES (NULL), (0), (1), (2), (3) AS tab(col);
+-------------------------+
|count_if(((col % 2) = 0))|
+-------------------------+
|                        2|
+-------------------------+

SELECT count_if(col IS NULL) FROM VALUES (NULL), (0), (1), (2), (3) AS tab(col);
+-----------------------+
|count_if((col IS NULL))|
+-----------------------+
|                      1|
+-----------------------+

-- count_min_sketch
SELECT hex(count_min_sketch(col, 0.5d, 0.5d, 1)) FROM VALUES (1), (2), (1) AS tab(col);
+---------------------------------------+
|hex(count_min_sketch(col, 0.5, 0.5, 1))|
+---------------------------------------+
|                   00000001000000000...|
+---------------------------------------+

-- covar_pop
SELECT covar_pop(c1, c2) FROM VALUES (1,1), (2,2), (3,3) AS tab(c1, c2);
+------------------+
| covar_pop(c1, c2)|
+------------------+
|0.6666666666666666|
+------------------+

-- covar_samp
SELECT covar_samp(c1, c2) FROM VALUES (1,1), (2,2), (3,3) AS tab(c1, c2);
+------------------+
|covar_samp(c1, c2)|
+------------------+
|               1.0|
+------------------+

-- every
SELECT every(col) FROM VALUES (true), (true), (true) AS tab(col);
+----------+
|every(col)|
+----------+
|      true|
+----------+

SELECT every(col) FROM VALUES (NULL), (true), (true) AS tab(col);
+----------+
|every(col)|
+----------+
|      true|
+----------+

SELECT every(col) FROM VALUES (true), (false), (true) AS tab(col);
+----------+
|every(col)|
+----------+
|     false|
+----------+

-- first
SELECT first(col) FROM VALUES (10), (5), (20) AS tab(col);
+----------+
|first(col)|
+----------+
|        10|
+----------+

SELECT first(col) FROM VALUES (NULL), (5), (20) AS tab(col);
+----------+
|first(col)|
+----------+
|      NULL|
+----------+

SELECT first(col, true) FROM VALUES (NULL), (5), (20) AS tab(col);
+----------+
|first(col)|
+----------+
|         5|
+----------+

-- first_value
SELECT first_value(col) FROM VALUES (10), (5), (20) AS tab(col);
+----------------+
|first_value(col)|
+----------------+
|              10|
+----------------+

SELECT first_value(col) FROM VALUES (NULL), (5), (20) AS tab(col);
+----------------+
|first_value(col)|
+----------------+
|            NULL|
+----------------+

SELECT first_value(col, true) FROM VALUES (NULL), (5), (20) AS tab(col);
+----------------+
|first_value(col)|
+----------------+
|               5|
+----------------+

-- grouping
SELECT name, grouping(name), sum(age) FROM VALUES (2, 'Alice'), (5, 'Bob') people(age, name) GROUP BY cube(name);
+-----+--------------+--------+
| name|grouping(name)|sum(age)|
+-----+--------------+--------+
| NULL|             1|       7|
|Alice|             0|       2|
|  Bob|             0|       5|
+-----+--------------+--------+

-- grouping_id
SELECT name, grouping_id(), sum(age), avg(height) FROM VALUES (2, 'Alice', 165), (5, 'Bob', 180) people(age, name, height) GROUP BY cube(name, height);
+-----+-------------+--------+-----------+
| name|grouping_id()|sum(age)|avg(height)|
+-----+-------------+--------+-----------+
| NULL|            2|       2|      165.0|
|Alice|            0|       2|      165.0|
|Alice|            1|       2|      165.0|
| NULL|            3|       7|      172.5|
|  Bob|            1|       5|      180.0|
|  Bob|            0|       5|      180.0|
| NULL|            2|       5|      180.0|
+-----+-------------+--------+-----------+

-- histogram_numeric
SELECT histogram_numeric(col, 5) FROM VALUES (0), (1), (2), (10) AS tab(col);
+-------------------------+
|histogram_numeric(col, 5)|
+-------------------------+
|     [{0, 1.0}, {1, 1....|
+-------------------------+

-- hll_sketch_agg
SELECT hll_sketch_estimate(hll_sketch_agg(col, 12)) FROM VALUES (1), (1), (2), (2), (3) tab(col);
+--------------------------------------------+
|hll_sketch_estimate(hll_sketch_agg(col, 12))|
+--------------------------------------------+
|                                           3|
+--------------------------------------------+

-- hll_union_agg
SELECT hll_sketch_estimate(hll_union_agg(sketch, true)) FROM (SELECT hll_sketch_agg(col) as sketch FROM VALUES (1) tab(col) UNION ALL SELECT hll_sketch_agg(col, 20) as sketch FROM VALUES (1) tab(col));
+------------------------------------------------+
|hll_sketch_estimate(hll_union_agg(sketch, true))|
+------------------------------------------------+
|                                               1|
+------------------------------------------------+

-- kurtosis
SELECT kurtosis(col) FROM VALUES (-10), (-20), (100), (1000) AS tab(col);
+-------------------+
|      kurtosis(col)|
+-------------------+
|-0.7014368047529618|
+-------------------+

SELECT kurtosis(col) FROM VALUES (1), (10), (100), (10), (1) as tab(col);
+-------------------+
|      kurtosis(col)|
+-------------------+
|0.19432323191698986|
+-------------------+

-- last
SELECT last(col) FROM VALUES (10), (5), (20) AS tab(col);
+---------+
|last(col)|
+---------+
|       20|
+---------+

SELECT last(col) FROM VALUES (10), (5), (NULL) AS tab(col);
+---------+
|last(col)|
+---------+
|     NULL|
+---------+

SELECT last(col, true) FROM VALUES (10), (5), (NULL) AS tab(col);
+---------+
|last(col)|
+---------+
|        5|
+---------+

-- last_value
SELECT last_value(col) FROM VALUES (10), (5), (20) AS tab(col);
+---------------+
|last_value(col)|
+---------------+
|             20|
+---------------+

SELECT last_value(col) FROM VALUES (10), (5), (NULL) AS tab(col);
+---------------+
|last_value(col)|
+---------------+
|           NULL|
+---------------+

SELECT last_value(col, true) FROM VALUES (10), (5), (NULL) AS tab(col);
+---------------+
|last_value(col)|
+---------------+
|              5|
+---------------+

-- max
SELECT max(col) FROM VALUES (10), (50), (20) AS tab(col);
+--------+
|max(col)|
+--------+
|      50|
+--------+

-- max_by
SELECT max_by(x, y) FROM VALUES ('a', 10), ('b', 50), ('c', 20) AS tab(x, y);
+------------+
|max_by(x, y)|
+------------+
|           b|
+------------+

-- mean
SELECT mean(col) FROM VALUES (1), (2), (3) AS tab(col);
+---------+
|mean(col)|
+---------+
|      2.0|
+---------+

SELECT mean(col) FROM VALUES (1), (2), (NULL) AS tab(col);
+---------+
|mean(col)|
+---------+
|      1.5|
+---------+

-- median
SELECT median(col) FROM VALUES (0), (10) AS tab(col);
+-----------+
|median(col)|
+-----------+
|        5.0|
+-----------+

SELECT median(col) FROM VALUES (INTERVAL '0' MONTH), (INTERVAL '10' MONTH) AS tab(col);
+--------------------+
|         median(col)|
+--------------------+
|INTERVAL '0-5' YE...|
+--------------------+

-- min
SELECT min(col) FROM VALUES (10), (-1), (20) AS tab(col);
+--------+
|min(col)|
+--------+
|      -1|
+--------+

-- min_by
SELECT min_by(x, y) FROM VALUES ('a', 10), ('b', 50), ('c', 20) AS tab(x, y);
+------------+
|min_by(x, y)|
+------------+
|           a|
+------------+

-- mode
SELECT mode(col) FROM VALUES (0), (10), (10) AS tab(col);
+---------+
|mode(col)|
+---------+
|       10|
+---------+

SELECT mode(col) FROM VALUES (INTERVAL '0' MONTH), (INTERVAL '10' MONTH), (INTERVAL '10' MONTH) AS tab(col);
+-------------------+
|          mode(col)|
+-------------------+
|INTERVAL '10' MONTH|
+-------------------+

SELECT mode(col) FROM VALUES (0), (10), (10), (null), (null), (null) AS tab(col);
+---------+
|mode(col)|
+---------+
|       10|
+---------+

-- percentile
SELECT percentile(col, 0.3) FROM VALUES (0), (10) AS tab(col);
+-----------------------+
|percentile(col, 0.3, 1)|
+-----------------------+
|                    3.0|
+-----------------------+

SELECT percentile(col, array(0.25, 0.75)) FROM VALUES (0), (10) AS tab(col);
+-------------------------------------+
|percentile(col, array(0.25, 0.75), 1)|
+-------------------------------------+
|                           [2.5, 7.5]|
+-------------------------------------+

SELECT percentile(col, 0.5) FROM VALUES (INTERVAL '0' MONTH), (INTERVAL '10' MONTH) AS tab(col);
+-----------------------+
|percentile(col, 0.5, 1)|
+-----------------------+
|   INTERVAL '0-5' YE...|
+-----------------------+

SELECT percentile(col, array(0.2, 0.5)) FROM VALUES (INTERVAL '0' SECOND), (INTERVAL '10' SECOND) AS tab(col);
+-----------------------------------+
|percentile(col, array(0.2, 0.5), 1)|
+-----------------------------------+
|               [INTERVAL '0 00:0...'|
+-----------------------------------+

-- percentile_approx
SELECT percentile_approx(col, array(0.5, 0.4, 0.1), 100) FROM VALUES (0), (1), (2), (10) AS tab(col);
+-------------------------------------------------+
|percentile_approx(col, array(0.5, 0.4, 0.1), 100)|
+-------------------------------------------------+
|                                        [1, 1, 0]|
+-------------------------------------------------+

SELECT percentile_approx(col, 0.5, 100) FROM VALUES (0), (6), (7), (9), (10) AS tab(col);
+--------------------------------+
|percentile_approx(col, 0.5, 100)|
+--------------------------------+
|                               7|
+--------------------------------+

SELECT percentile_approx(col, 0.5, 100) FROM VALUES (INTERVAL '0' MONTH), (INTERVAL '1' MONTH), (INTERVAL '2' MONTH), (INTERVAL '10' MONTH) AS tab(col);
+--------------------------------+
|percentile_approx(col, 0.5, 100)|
+--------------------------------+
|              INTERVAL '1' MONTH|
+--------------------------------+

SELECT percentile_approx(col, array(0.5, 0.7), 100) FROM VALUES (INTERVAL '0' SECOND), (INTERVAL '1' SECOND), (INTERVAL '2' SECOND), (INTERVAL '10' SECOND) AS tab(col);
+--------------------------------------------+
|percentile_approx(col, array(0.5, 0.7), 100)|
+--------------------------------------------+
|                        [INTERVAL '01' SE...|
+--------------------------------------------+

-- regr_avgx
SELECT regr_avgx(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+---------------+
|regr_avgx(y, x)|
+---------------+
|           2.75|
+---------------+

SELECT regr_avgx(y, x) FROM VALUES (1, null) AS tab(y, x);
+---------------+
|regr_avgx(y, x)|
+---------------+
|           NULL|
+---------------+

SELECT regr_avgx(y, x) FROM VALUES (null, 1) AS tab(y, x);
+---------------+
|regr_avgx(y, x)|
+---------------+
|           NULL|
+---------------+

SELECT regr_avgx(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+---------------+
|regr_avgx(y, x)|
+---------------+
|            3.0|
+---------------+

SELECT regr_avgx(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+---------------+
|regr_avgx(y, x)|
+---------------+
|            3.0|
+---------------+

-- regr_avgy
SELECT regr_avgy(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+---------------+
|regr_avgy(y, x)|
+---------------+
|           1.75|
+---------------+

SELECT regr_avgy(y, x) FROM VALUES (1, null) AS tab(y, x);
+---------------+
|regr_avgy(y, x)|
+---------------+
|           NULL|
+---------------+

SELECT regr_avgy(y, x) FROM VALUES (null, 1) AS tab(y, x);
+---------------+
|regr_avgy(y, x)|
+---------------+
|           NULL|
+---------------+

SELECT regr_avgy(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|   regr_avgy(y, x)|
+------------------+
|1.6666666666666667|
+------------------+

SELECT regr_avgy(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+---------------+
|regr_avgy(y, x)|
+---------------+
|            1.5|
+---------------+

-- regr_count
SELECT regr_count(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+----------------+
|regr_count(y, x)|
+----------------+
|               4|
+----------------+

SELECT regr_count(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+----------------+
|regr_count(y, x)|
+----------------+
|               3|
+----------------+

SELECT regr_count(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+----------------+
|regr_count(y, x)|
+----------------+
|               2|
+----------------+

-- regr_intercept
SELECT regr_intercept(y, x) FROM VALUES (1,1), (2,2), (3,3) AS tab(y, x);
+--------------------+
|regr_intercept(y, x)|
+--------------------+
|                 0.0|
+--------------------+

SELECT regr_intercept(y, x) FROM VALUES (1, null) AS tab(y, x);
+--------------------+
|regr_intercept(y, x)|
+--------------------+
|                NULL|
+--------------------+

SELECT regr_intercept(y, x) FROM VALUES (null, 1) AS tab(y, x);
+--------------------+
|regr_intercept(y, x)|
+--------------------+
|                NULL|
+--------------------+

-- regr_r2
SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|     regr_r2(y, x)|
+------------------+
|0.2727272727272726|
+------------------+

SELECT regr_r2(y, x) FROM VALUES (1, null) AS tab(y, x);
+-------------+
|regr_r2(y, x)|
+-------------+
|         NULL|
+-------------+

SELECT regr_r2(y, x) FROM VALUES (null, 1) AS tab(y, x);
+-------------+
|regr_r2(y, x)|
+-------------+
|         NULL|
+-------------+

SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|     regr_r2(y, x)|
+------------------+
|0.7500000000000001|
+------------------+

SELECT regr_r2(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+-------------+
|regr_r2(y, x)|
+-------------+
|          1.0|
+-------------+

-- regr_slope
SELECT regr_slope(y, x) FROM VALUES (1,1), (2,2), (3,3) AS tab(y, x);
+----------------+
|regr_slope(y, x)|
+----------------+
|             1.0|
+----------------+

SELECT regr_slope(y, x) FROM VALUES (1, null) AS tab(y, x);
+----------------+
|regr_slope(y, x)|
+----------------+
|            NULL|
+----------------+

SELECT regr_slope(y, x) FROM VALUES (null, 1) AS tab(y, x);
+----------------+
|regr_slope(y, x)|
+----------------+
|            NULL|
+----------------+

-- regr_sxx
SELECT regr_sxx(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|    regr_sxx(y, x)|
+------------------+
|2.7499999999999996|
+------------------+

SELECT regr_sxx(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+--------------+
|regr_sxx(y, x)|
+--------------+
|           2.0|
+--------------+

SELECT regr_sxx(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+--------------+
|regr_sxx(y, x)|
+--------------+
|           2.0|
+--------------+

-- regr_sxy
SELECT regr_sxy(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|    regr_sxy(y, x)|
+------------------+
|0.7499999999999998|
+------------------+

SELECT regr_sxy(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+--------------+
|regr_sxy(y, x)|
+--------------+
|           1.0|
+--------------+

SELECT regr_sxy(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+--------------+
|regr_sxy(y, x)|
+--------------+
|           1.0|
+--------------+

-- regr_syy
SELECT regr_syy(y, x) FROM VALUES (1, 2), (2, 2), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|    regr_syy(y, x)|
+------------------+
|0.7499999999999999|
+------------------+

SELECT regr_syy(y, x) FROM VALUES (1, 2), (2, null), (2, 3), (2, 4) AS tab(y, x);
+------------------+
|    regr_syy(y, x)|
+------------------+
|0.6666666666666666|
+------------------+

SELECT regr_syy(y, x) FROM VALUES (1, 2), (2, null), (null, 3), (2, 4) AS tab(y, x);
+--------------+
|regr_syy(y, x)|
+--------------+
|           0.5|
+--------------+

-- skewness
SELECT skewness(col) FROM VALUES (-10), (-20), (100), (1000) AS tab(col);
+------------------+
|     skewness(col)|
+------------------+
|1.1135657469022013|
+------------------+

SELECT skewness(col) FROM VALUES (-1000), (-100), (10), (20) AS tab(col);
+-------------------+
|      skewness(col)|
+-------------------+
|-1.1135657469022011|
+-------------------+

-- some
SELECT some(col) FROM VALUES (true), (false), (false) AS tab(col);
+---------+
|some(col)|
+---------+
|     true|
+---------+

SELECT some(col) FROM VALUES (NULL), (true), (false) AS tab(col);
+---------+
|some(col)|
+---------+
|     true|
+---------+

SELECT some(col) FROM VALUES (false), (false), (NULL) AS tab(col);
+---------+
|some(col)|
+---------+
|    false|
+---------+

-- std
SELECT std(col) FROM VALUES (1), (2), (3) AS tab(col);
+--------+
|std(col)|
+--------+
|     1.0|
+--------+

-- stddev
SELECT stddev(col) FROM VALUES (1), (2), (3) AS tab(col);
+-----------+
|stddev(col)|
+-----------+
|        1.0|
+-----------+

-- stddev_pop
SELECT stddev_pop(col) FROM VALUES (1), (2), (3) AS tab(col);
+-----------------+
|  stddev_pop(col)|
+-----------------+
|0.816496580927726|
+-----------------+

-- stddev_samp
SELECT stddev_samp(col) FROM VALUES (1), (2), (3) AS tab(col);
+----------------+
|stddev_samp(col)|
+----------------+
|             1.0|
+----------------+

-- sum
SELECT sum(col) FROM VALUES (5), (10), (15) AS tab(col);
+--------+
|sum(col)|
+--------+
|      30|
+--------+

SELECT sum(col) FROM VALUES (NULL), (10), (15) AS tab(col);
+--------+
|sum(col)|
+--------+
|      25|
+--------+

SELECT sum(col) FROM VALUES (NULL), (NULL) AS tab(col);
+--------+
|sum(col)|
+--------+
|    NULL|
+--------+

-- try_avg
SELECT try_avg(col) FROM VALUES (1), (2), (3) AS tab(col);
+------------+
|try_avg(col)|
+------------+
|         2.0|
+------------+

SELECT try_avg(col) FROM VALUES (1), (2), (NULL) AS tab(col);
+------------+
|try_avg(col)|
+------------+
|         1.5|
+------------+

SELECT try_avg(col) FROM VALUES (interval '2147483647 months'), (interval '1 months') AS tab(col);
+------------+
|try_avg(col)|
+------------+
|        NULL|
+------------+

-- try_sum
SELECT try_sum(col) FROM VALUES (5), (10), (15) AS tab(col);
+------------+
|try_sum(col)|
+------------+
|          30|
+------------+

SELECT try_sum(col) FROM VALUES (NULL), (10), (15) AS tab(col);
+------------+
|try_sum(col)|
+------------+
|          25|
+------------+

SELECT try_sum(col) FROM VALUES (NULL), (NULL) AS tab(col);
+------------+
|try_sum(col)|
+------------+
|        NULL|
+------------+

SELECT try_sum(col) FROM VALUES (9223372036854775807L), (1L) AS tab(col);
+------------+
|try_sum(col)|
+------------+
|        NULL|
+------------+

-- var_pop
SELECT var_pop(col) FROM VALUES (1), (2), (3) AS tab(col);
+------------------+
|      var_pop(col)|
+------------------+
|0.6666666666666666|
+------------------+

-- var_samp
SELECT var_samp(col) FROM VALUES (1), (2), (3) AS tab(col);
+-------------+
|var_samp(col)|
+-------------+
|          1.0|
+-------------+

-- variance
SELECT variance(col) FROM VALUES (1), (2), (3) AS tab(col);
+-------------+
|variance(col)|
+-------------+
|          1.0|
+-------------+
Spark SQL----内置函数Aggregate Functions

Spark SQL----内置函数Aggregate Functions

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