mysql - 行を省略せずに 2 つのクエリを組み合わせる

Question

2 つのテーブルがあり、これら両方のテーブルのレコードが必要です。

クエリ 1

SELECT SUM(rec_issued) AS issed,
       regen_id,
       YEAR(issue_date) AS iYear,
       MONTH(issue_date) AS iMonth
FROM `view_rec_issued`
WHERE `regen_id` = 2
GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC
ORDER BY issue_date ASC

次の結果が得られます。

| issed | regen_id | iYear | iMonth |
-------------------------------------
|   424 |        2 |  2011 |      3 |
|  4340 |        2 |  2011 |      4 |
|  4235 |        2 |  2011 |      5 |
| 10570 |        2 |  2012 |      2 |
|  4761 |        2 |  2012 |      3 |
|  5000 |        2 |  2012 |      4 |
|  3700 |        2 |  2012 |      5 |
|  3414 |        2 |  2012 |      6 |
|  3700 |        2 |  2012 |      7 |
|  2992 |        2 |  2012 |      8 |
|   995 |        2 |  2012 |     10 |

クエリ 2

SELECT SUM(total_redem) AS redemed,
       regen_id,
       YEAR(redemption_date) AS rYear,
       MONTH(redemption_date) AS rMonth
FROM `recredem_month_wise`
WHERE `regen_id` = 2
GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC
order by redemption_date ASC

次の結果が得られます。

| redemed | regen_id | rYear | rMonth |
---------------------------------------
|     424 |        2 |  2011 |      3 |
|     260 |        2 |  2011 |      4 |
|    6523 |        2 |  2011 |      5 |
|    1070 |        2 |  2011 |      6 |
|     200 |        2 |  2011 |     10 |
|     500 |        2 |  2011 |     11 |
|    9750 |        2 |  2012 |      2 |
|    5000 |        2 |  2012 |      3 |
|    5500 |        2 |  2012 |      4 |
|    3803 |        2 |  2012 |      5 |
|    3700 |        2 |  2012 |      7 |
|    3000 |        2 |  2012 |      8 |

望ましい結果

しかし、私はこのようにしたい:

|  issed | regen_id |  iYear | iMonth | redemed | regen_id |  rYear | rMonth |
-------------------------------------------------------------------------------
|    424 |        2 |   2011 |      3 |     424 |        2 |   2011 |      3 |
|   4340 |        2 |   2011 |      4 |     260 |        2 |   2011 |      4 |
|   4235 |        2 |   2011 |      5 |    6523 |        2 |   2011 |      5 |
|   NULL |     NULL |   NULL |   NULL |    1070 |        2 |   2011 |      6 |
|   NULL |     NULL |   NULL |   NULL |     200 |        2 |   2011 |     10 |
|   NULL |     NULL |   NULL |   NULL |     500 |        2 |   2011 |     11 |
|  10570 |        2 |   2012 |      2 |    9750 |        2 |   2012 |      2 |
|   4761 |        2 |   2012 |      3 |    5000 |        2 |   2012 |      3 |
|   5000 |        2 |   2012 |      4 |    5500 |        2 |   2012 |      4 |
|   3700 |        2 |   2012 |      5 |    3803 |        2 |   2012 |      5 |
|   3414 |        2 |   2012 |      6 |    NULL |     NULL |   NULL |   NULL |
|   3700 |        2 |   2012 |      7 |    3700 |        2 |   2012 |      7 |
|   2992 |        2 |   2012 |      8 |    3000 |        2 |   2012 |      8 |
|    995 |        2 |   2012 |     10 |    NULL |     NULL |   NULL |   NULL |

これらのテーブルregen_idでは一意であり、YEARおよびとしてデータが必要MONTHです。1 つのテーブルに特定の月と年にレコードがない場合は、0 またはを取得する必要がありますNULL。

しかし、すべての記録において、年と月は次のように等しいはずです -

 iYear = rYear and iMonth = rMonth

したがって、両方のフィールドをマージできます-年と月を2回表示する必要はありません

iYear and rYear = year
iMonth and rMonth = month

アップデート

このクエリを試してみましたが、問題はほぼ解決しましたが、レコードは「YEAR DESC、MONTH DESC」という形式でソートされていません。

SELECT DISTINCT A.issed, A.regen_id, A.iYear AS yrs, A.iMonth AS mnt, B.redemed, B.regen_id, B.rYear AS yrs, B.rMonth AS mnt
FROM(SELECT SUM(rec_issued) AS issed, regen_id, YEAR(issue_date) AS iYear, MONTH(issue_date) AS iMonth  
FROM `view_rec_issued` 
WHERE `regen_id` = 2 
GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC 
ORDER BY issue_date ASC) AS A 
LEFT JOIN 
(SELECT SUM(total_redem) AS redemed, regen_id, YEAR(redemption_date) AS rYear, MONTH(redemption_date) AS rMonth
FROM `recredem_month_wise` 
WHERE `regen_id` = 2 
GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC 
ORDER BY redemption_date ASC) AS B ON A.iYear = B.rYear AND A.iMonth = B.rMonth

UNION

SELECT DISTINCT A.issed, A.regen_id, A.iYear AS yrs, A.iMonth AS mnt, B.redemed, B.regen_id, B.rYear AS yrs, B.rMonth AS mnt
FROM(SELECT SUM(rec_issued) AS issed, regen_id, YEAR(issue_date) AS iYear, MONTH(issue_date) AS iMonth  
FROM `view_rec_issued` 
WHERE `regen_id` = 2 
GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC 
ORDER BY issue_date ASC) AS A 
RIGHT JOIN 
(SELECT SUM(total_redem) AS redemed, regen_id, YEAR(redemption_date) AS rYear, MONTH(redemption_date) AS rMonth 
FROM `recredem_month_wise` 
WHERE `regen_id` = 2 
GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC 
ORDER BY redemption_date ASC) AS B ON A.iYear = B.rYear AND A.iMonth = B.rMonth

score 1 · Accepted Answer

あなたが説明するものは a と呼ばれます: 両方のテーブルのすべての行が必要で、一致が見つからない場合FULL OUTER JOINは他のテーブルが埋められます。NULL残念ながら、MySQL は完全な外部結合を提供していないため、シミュレートする必要があります。

MySQL の完全外部結合も参照してください。

正規の方法で完全外部結合をエミュレートする

NULLこれを記述する 1 つの方法は次のようになります。これは、一致がない場合に生成されます。

(SELECT I.iYear AS `year`, I.iMonth AS `month`, I.issed, R.redeemed
 FROM (
  SELECT SUM(rec_issued) AS issed,
         regen_id,
         YEAR(issue_date) AS iYear,
         MONTH(issue_date) AS iMonth
  FROM `view_rec_issued`
  WHERE `regen_id` = 2
  GROUP BY YEAR(issue_date), MONTH(issue_date)
 ) I
 LEFT JOIN (
  SELECT SUM(total_redem) AS redemed,
         regen_id,
         YEAR(redemption_date) AS rYear,
         MONTH(redemption_date) AS rMonth
  FROM `recredem_month_wise`
  WHERE `regen_id` = 2
  GROUP BY YEAR(redemption_date), MONTH(redemption_date)
 ) R
 ON (I.iYear = R.rYear AND I.iMonth = R.rMonth)
)
UNION DISTINCT
(SELECT R.iYear AS `year`, R.iMonth AS `month`, I.issed, R.redeemed
 FROM (
  SELECT SUM(total_redem) AS redemed,
         regen_id,
         YEAR(redemption_date) AS rYear,
         MONTH(redemption_date) AS rMonth
  FROM `recredem_month_wise`
  WHERE `regen_id` = 2
  GROUP BY YEAR(redemption_date), MONTH(redemption_date)
 ) R
 LEFT JOIN (
  SELECT SUM(rec_issued) AS issed,
         regen_id,
         YEAR(issue_date) AS iYear,
         MONTH(issue_date) AS iMonth
  FROM `view_rec_issued`
  WHERE `regen_id` = 2
  GROUP BY YEAR(issue_date), MONTH(issue_date)
 ) I
 ON (I.iYear = R.rYear AND I.iMonth = R.rMonth)
)
ORDER BY `year` ASC, `month` ASC

これに含まれるサブクエリのビューを記述することでこれを短くすることができますが、変更できるようにしたい場合regen_id、これは依然としてかなりかさばるコードになります。

ゼロとの和集合

外部結合を完全に回避し、代わりに個別の結合を使用して、次のように行にゼロを埋めることで、物事をはるかに簡単にすることができます。

SELECT YEAR(`date`) AS `year`, MONTH(`date`) AS `month`,
       SUM(rec_issued) AS issued, SUM(total_redem) AS redeemed
FROM (
    SELECT issue_date AS `date`, rec_issued, 0 AS total_redem
    FROM view_rec_issued WHERE regen_id = 2
  UNION ALL
    SELECT redemption_date AS `date`, 0 AS rec_issued, total_redem
    FROM redemption_month_wise WHERE regen_id = 2
  ) AS U
GROUP BY EXTRACT(YEAR_MONTH FROM `date`) ASC

左結合すべてをサブクエリ検索月に

次のテーブルでは、いずれかのテーブルで発生する日付を検索するためだけに外部結合シミュレーションを実行します。次に、左結合を実行して合計を計算します。その結果、NULL欠損値の代わりにゼロが返されます。

SELECT LEFT(DI.ym, 4) + 0 AS `year`, RIGHT(DI.ym, 2) + 0 AS `month`,
       DI.issed, SUM(R.total_redem) AS redeemed
FROM
 (SELECT D.ym, SUM(I.rec_issued) AS issed
  FROM
   (SELECT DISTINCT EXTRACT(YEAR_MONTH FROM issue_date) as ym
    FROM view_rec_issued
    WHERE regen_id = 2
   UNION DISTINCT
    SELECT DISTINCT EXTRACT(YEAR_MONTH FROM redemtion_date) AS ym
    FROM recredem_month_wise
    WHERE regen_id = 2
   ) AS D
  LEFT JOIN view_rec_issued AS I
         ON I.regen_id = 2
        AND EXTRACT(YEAR_MONTH FROM I.issue_date) = D.ym
 ) AS DI
LEFT JOIN recredem_month_wise AS R
       ON R.regen_id = 2
      AND EXTRACT(YEAR_MONTH FROM R.redemtion_date) = DI.ym
GROUP BY DI.ym ASC

これは、上記のクエリよりも各テーブルを 1 回ずつ 2 回調べる必要があるため、処理が遅くなる可能性があります。パフォーマンスが心配な場合は、両方を試してベンチマークしてください。コードの長さの点では、このクエリははるかにコンパクトで、読みやすいと思います。

上記のクエリは、この投稿の過去の改訂版では異なっていたことに注意してください。そのバージョンは subquery を省略しましたDI。結果は読みやすくなりましたが、残念ながら間違っていました。1 か月に 2 回の発行があり、3 回の償還があった場合、結合はこれをその月の 6 行に結合し、すべての発行を 3 回、各償還を 2 回カウントします。

これまでのところ、すべてのクエリはテストされていません。あなたの質問にhttp://sqlfiddle.com/のサンプルデータが付属していた場合、ここに投稿する前にそこでクエリを試したはずです。

score 0 · Accepted Answer

次の順序でこれを試してください。

SELECT * FROM 
(SELECT DISTINCT A.issed, A.regen_id, A.iYear, A.iMonth, B.redemed, B.regen_id, B.rYear, B.rMonth
FROM (SELECT SUM(rec_issued) AS issed, regen_id, YEAR(issue_date) AS iYear, MONTH(issue_date) AS iMonth  
FROM `view_rec_issued` 
WHERE `regen_id` = 2 
GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC 
ORDER BY issue_date ASC) AS A 
LEFT JOIN 
(SELECT SUM(total_redem) AS redemed, regen_id, YEAR(redemption_date) AS rYear, MONTH(redemption_date) AS rMonth 
FROM `recredem_month_wise` 
WHERE `regen_id` = 2 
GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC 
ORDER BY redemption_date ASC) AS B ON A.iYear = B.rYear AND A.iMonth = B.rMonth
UNION 
SELECT DISTINCT A.issed, A.regen_id, A.iYear, A.iMonth, B.redemed, B.regen_id, B.rYear, B.rMonth
FROM (SELECT SUM(rec_issued) AS issed, regen_id, YEAR(issue_date) AS iYear, MONTH(issue_date) AS iMonth  
FROM `view_rec_issued` 
WHERE `regen_id` = 2 
GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC 
ORDER BY issue_date ASC) AS A 
RIGHT JOIN 
(SELECT SUM(total_redem) AS redemed, regen_id, YEAR(redemption_date) AS rYear, MONTH(redemption_date) AS rMonth 
FROM `recredem_month_wise` 
WHERE `regen_id` = 2 
GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC 
ORDER BY redemption_date ASC) AS B ON A.iYear = B.rYear AND A.iMonth = B.rMonth) AS C
ORDER BY iYear DESC, iMonth DESC