PIVOT 句

適用対象:「はい」のチェック マーク Databricks SQL 「はい」のチェック マーク 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

  • aggregate_expression

    すべての列参照 table_reference集計関数の引数である任意の型の式。

  • agg_column_alias

    集計結果の別名 (省略可能)。 別名が指定されていない場合、PIVOTaggregate_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。

  • expression_list

    column_list から列の別名に値をマップします。

    • expression

      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。 式がリテラルでない場合、Azure Databricksは NON_LITERAL_PIVOT_VALUES を発生させます。 型が一致しない場合、Azure Databricksは PIVOT_VALUE_DATA_TYPE_MISMATCH を発生させます。

      各タプルのの数は、column_namescolumn_list の数と一致している必要があります。

    • column_alias

      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、PIVOTexpression 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。

一般的なエラー状態

-- 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));
 year  region  q1   q2   q3  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;
 year  region  q1   q2   q3  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

-- 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));
 year  q1_east  q1_west  q2_east  q2_west  q3_east  q3_west  q4_east  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;
 year  q1_east  q1_west  q2_east  q2_west  q3_east  q3_west  q4_east  q4_west
 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));
  year   q1   q2   q3   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;
  year   q1   q2   q3   q4
  2018  205   45   85   85
  2019  245  225  165  125

-- 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));
 year  q1_total  q1_avg  q2_total  q2_avg  q3_total  q3_avg  q4_total  q4_avg
 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;
 year  q1_total  q1_avg  q2_total  q2_avg  q3_total  q3_avg  q4_total  q4_avg
 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

-- Pivot values must be literals.
> SELECT * FROM sales
  PIVOT (sum(sales) FOR quarter IN (1 + 0 AS q1));
  Error: NON_LITERAL_PIVOT_VALUES