適用対象:
Databricks SQL
Databricks Runtime
指定した列リストの一意の値を個別の列に回転することによって、上記の table_reference の行を変換します。
構文
PIVOT ( { aggregate_expression [ [ AS ] agg_column_alias ] } [, ...]
FOR column_list IN ( expression_list ) )
column_list
{ column_name |
( column_name [, ...] ) }
expression_list
{ expression [ AS ] [ column_alias ] |
{ ( expression [, ...] ) [ AS ] [ column_alias] } [, ...] ) }
パラメーター
-
すべての列参照
table_referenceが集計関数の引数である任意の型の式。 -
集計結果の別名 (省略可能)。 別名が指定されていない場合、
PIVOTはaggregate_expressionに基づいて別名を生成します。 column_list
回転する列のセット。
-
table_referenceからの列。
-
expression_list
column_listから列の別名に値をマップします。-
それぞれの
column_nameと最も一般的でない型を共有する型のリテラル式。各タプルの式の数は、
column_namesのcolumn_listの数と一致している必要があります。 -
生成された列の名前を指定する省略可能な別名。 別名が指定されていない場合、
PIVOTはexpressionに基づいて別名を生成します。
-
結果
次の形式の一時テーブルとなります。
table_referenceまたはaggregate_expressionで指定されていないcolumn_listの中間結果セットのすべての列。これらの列により、列がグループ化されます。
expressionのタプルとaggregate_expressionの組み合わせごとに、PIVOTは 1 つの列を生成します。 型はaggregate_expressionの型となります。aggregate_expressionが 1 つだけの場合、column_aliasを使用して列に名前が付けられます。 それ以外の場合は、column_alias_agg_column_aliasという名前になります。各セルの値は、
aggregation_expressionを使用したFILTER ( WHERE column_list IN (expression, ...)の結果です。
例
-- A very basic PIVOT
-- Given a table with sales by quarter, return a table that returns sales across quarters per year.
> CREATE TEMP VIEW sales(year, quarter, region, sales) AS
VALUES (2018, 1, 'east', 100),
(2018, 2, 'east', 20),
(2018, 3, 'east', 40),
(2018, 4, 'east', 40),
(2019, 1, 'east', 120),
(2019, 2, 'east', 110),
(2019, 3, 'east', 80),
(2019, 4, 'east', 60),
(2018, 1, 'west', 105),
(2018, 2, 'west', 25),
(2018, 3, 'west', 45),
(2018, 4, 'west', 45),
(2019, 1, 'west', 125),
(2019, 2, 'west', 115),
(2019, 3, 'west', 85),
(2019, 4, 'west', 65);
> SELECT year, region, q1, q2, q3, q4
FROM sales
PIVOT (sum(sales) AS sales
FOR quarter
IN (1 AS q1, 2 AS q2, 3 AS q3, 4 AS q4));
2018 east 100 20 40 40
2019 east 120 110 80 60
2018 west 105 25 45 45
2019 west 125 115 85 65
-- The same query written without PIVOT
> SELECT year, region,
sum(sales) FILTER(WHERE quarter = 1) AS q1,
sum(sales) FILTER(WHERE quarter = 2) AS q2,
sum(sales) FILTER(WHERE quarter = 3) AS q2,
sum(sales) FILTER(WHERE quarter = 4) AS q4
FROM sales
GROUP BY year, region;
2018 east 100 20 40 40
2019 east 120 110 80 60
2018 west 105 25 45 45
2019 west 125 115 85 65
-- Also PIVOT on region
> SELECT year, q1_east, q1_west, q2_east, q2_west, q3_east, q3_west, q4_east, q4_west
FROM sales
PIVOT (sum(sales) AS sales
FOR (quarter, region)
IN ((1, 'east') AS q1_east, (1, 'west') AS q1_west, (2, 'east') AS q2_east, (2, 'west') AS q2_west,
(3, 'east') AS q3_east, (3, 'west') AS q3_west, (4, 'east') AS q4_east, (4, 'west') AS q4_west));
2018 100 105 20 25 40 45 40 45
2019 120 125 110 115 80 85 60 65
-- The same query written without PIVOT
> SELECT year,
sum(sales) FILTER(WHERE (quarter, region) IN ((1, 'east'))) AS q1_east,
sum(sales) FILTER(WHERE (quarter, region) IN ((1, 'west'))) AS q1_west,
sum(sales) FILTER(WHERE (quarter, region) IN ((2, 'east'))) AS q2_east,
sum(sales) FILTER(WHERE (quarter, region) IN ((2, 'west'))) AS q2_west,
sum(sales) FILTER(WHERE (quarter, region) IN ((3, 'east'))) AS q3_east,
sum(sales) FILTER(WHERE (quarter, region) IN ((3, 'west'))) AS q3_west,
sum(sales) FILTER(WHERE (quarter, region) IN ((4, 'east'))) AS q4_east,
sum(sales) FILTER(WHERE (quarter, region) IN ((4, 'west'))) AS q4_west
FROM sales
GROUP BY year;
2018 100 105 20 25 40 45 40 45
2019 120 125 110 115 80 85 60 65
-- To aggregate across regions the column must be removed from the input.
> SELECT year, q1, q2, q3, q4
FROM (SELECT year, quarter, sales FROM sales) AS s
PIVOT (sum(sales) AS sales
FOR quarter
IN (1 AS q1, 2 AS q2, 3 AS q3, 4 AS q4));
2018 205 45 85 85
2019 245 225 165 125
-- The same query without PIVOT
> SELECT year,
sum(sales) FILTER(WHERE quarter = 1) AS q1,
sum(sales) FILTER(WHERE quarter = 2) AS q2,
sum(sales) FILTER(WHERE quarter = 3) AS q3,
sum(sales) FILTER(WHERE quarter = 4) AS q4
FROM sales
GROUP BY year;
-- A PIVOT with multiple aggregations
> SELECT year, q1_total, q1_avg, q2_total, q2_avg, q3_total, q3_avg, q4_total, q4_avg
FROM (SELECT year, quarter, sales FROM sales) AS s
PIVOT (sum(sales) AS total, avg(sales) AS avg
FOR quarter
IN (1 AS q1, 2 AS q2, 3 AS q3, 4 AS q4));
2018 205 102.5 45 22.5 85 42.5 85 42.5
2019 245 122.5 225 112.5 165 82.5 125 62.5
-- The same query without PIVOT
> SELECT year,
sum(sales) FILTER(WHERE quarter = 1) AS q1_total,
avg(sales) FILTER(WHERE quarter = 1) AS q1_avg,
sum(sales) FILTER(WHERE quarter = 2) AS q2_total,
avg(sales) FILTER(WHERE quarter = 2) AS q2_avg,
sum(sales) FILTER(WHERE quarter = 3) AS q3_total,
avg(sales) FILTER(WHERE quarter = 3) AS q3_avg,
sum(sales) FILTER(WHERE quarter = 4) AS q4_total,
avg(sales) FILTER(WHERE quarter = 4) AS q4_avg
FROM sales
GROUP BY year;
2018 205 102.5 45 22.5 85 42.5 85 42.5
2019 245 122.5 225 112.5 165 82.5 125 62.5