SQL-根据列组合连续的日期行

假设我有以下 SQL 结果

BegDate | EndDate | quanitty
1/1/2014  1/31/2014    1
2/1/2014  2/28/2014    1
3/1/2014  3/31/2014    2
4/1/2014  4/30/2014    4
5/1/2014  5/31/2014    4
6/1/2014  6/30/2014    4
7/1/2014  7/31/2014    2
8/1/2014  8/30/2014    2

我需要将具有相同数量的所有月份分组到一行中，因此结果应该是

BegDate | EndDate | quanitty
1/1/2014  2/28/2014    1
3/1/2014  3/31/2014    2
4/1/2014  6/30/2014    4
7/1/2014  8/30/2014    2

我在 stackoverflow 上进行了搜索，发现了类似的帖子，我尝试过但没有解决该解决方案This https://stackoverflow.com/questions/24244659/group-consecutive-rows-of-same-value-using-time-spans and This https://stackoverflow.com/questions/23257246/combining-values-of-a-specific-column-from-consecutive-rows-in-sql

以下是我用来创建结果的 SQL，其中 term_start 是我的开始时间，term_end 是我的结束时间。如果您有任何建议，请告诉我。这是我在 SSRS 报告中使用的数据集，如果 SSRS 报告方面有更简单的方法来执行此操作，那么我愿意接受选项..谢谢！

SELECT 
collaboration = t.collaboration
, trade = t.trade
,  position = p.position
, buyer = CASE WHEN ((p.positiontype = 'BUY') OR (p.positiontype = 'SWAP' AND p.swaptype = 'BUY')) THEN co.name
                WHEN ((p.positiontype = 'SELL') OR (p.positiontype = 'SWAP' AND p.swaptype = 'SELL')) THEN cp.name
            END
, seller = CASE WHEN ((p.positiontype = 'SELL') OR (p.positiontype = 'SWAP' AND p.swaptype = 'SELL')) THEN co.name
                WHEN ((p.positiontype = 'BUY') OR (p.positiontype = 'SWAP' AND p.swaptype = 'BUY')) THEN cp.name 
            END
, trade_date = t.tradedate
, timezone = t.timezone
, delivery_point = isnull(pp.point,'')
------------TABLE DATA BELOW------------
, currency = f.currency
, currency_unit = f.unit
, term_start = CASE WHEN pq.quantitystatus = 'TRADE' THEN pq.begtime ELSE 0 END
, term_end = CASE WHEN pq.quantitystatus = 'TRADE' THEN dateadd(dd,-1,pq.endtime) ELSE 0 END 
, hours =   CASE 
            WHEN ls.loadshape is not null and ls.granularity = 'LOAD' and lsq.loadshape is not null THEN 'Hour Ending (HE) ' + CONVERT(VARCHAR,lsq.beghour + 1) + '00 through HE ' + CONVERT(VARCHAR, lsq.endhour) + '00 (' + CONVERT(VARCHAR, lsq.endhour-lsq.beghour-1) +' Hours each day), Monday Through Sunday, including NERC holidays; ' + tz.description
            WHEN ls.loadshape is not null and ls.granularity = 'LOAD' and lsq.loadshape is null THEN 'See attached schedule'
            WHEN ls.loadshape is not null and ls.granularity = 'PROFILE' THEN 'See attached schedule' 
            ELSE btz.cpn_description  END
, quantity = CASE 
            WHEN ls.loadshape is not null and ls.granularity = 'LOAD' and lsq.loadshape is not null THEN CONVERT(VARCHAR,convert(double precision, lsq.quantity))
            WHEN ls.loadshape is not null and ls.granularity = 'LOAD' and lsq.loadshape is null THEN 'See attached schedule'
            WHEN ls.loadshape is not null and ls.granularity = 'PROFILE' THEN 'See attached schedule' 
            ELSE CONVERT(VARCHAR,convert(double precision, pq.energy))   END    
, product = pr.producttype
, unit = CASE isnull(p.unit,'') WHEN 'dth' THEN 'Dth' WHEN 'kwh' THEN 'kWh' WHEN 'kwm' THEN 'kWm' WHEN 'mmbtu' THEN 'MMBtu' WHEN 'mw' THEN 'MW' when 'mwd' THEN 'MWD' WHEN 'mwh' THEN 'MWH' WHEN 'mwm' THEN 'MWM' WHEN 'gal' THEN 'Gallon' ELSE isnull(p.unit,'') END 
, unit_plural = CASE isnull(p.unit,'') WHEN 'dth' THEN 'Dth' WHEN 'kwh' THEN 'kWh' WHEN 'kwm' THEN 'kWm' WHEN 'mmbtu' THEN 'MMBtu''s' WHEN 'mw' THEN 'MW' when 'mwd' THEN 'MWD' WHEN 'mwh' THEN 'MWH' WHEN 'mwm' THEN 'MWM'  WHEN 'gal' THEN 'Gallons' ELSE isnull(p.unit,'') END 
, total_qty = convert(double precision, pp.totalquantity)
, priceindex = f.priceindex
, pricediff = convert(double precision, f.pricediff) 
, price = CASE 
            WHEN t.tradetype = 'Phys Power HR' or t.tradetype = 'Phys HR Power Option' and f.priceindex is not null THEN priceindex + '*' + convert(varchar, convert(double precision, factor))
            WHEN t.tradetype = 'Phys Power HR' or t.tradetype = 'Phys HR Power Option' and f.priceindex is null THEN convert(varchar, convert(double precision, f.pricediff))
    WHEN f.priceindex is not null and f.pricediff is null THEN f.priceindex 
            WHEN f.priceindex is not null and isnull(CONVERT(FLOAT, f.pricediff), 0) > 0 THEN f.priceindex + '+' + convert(varchar(max), convert(double precision, f.pricediff))
            WHEN f.priceindex is not null and isnull(CONVERT(FLOAT, f.pricediff), 0) < 0 THEN f.priceindex + '-' + convert(varchar(max), convert(double precision, f.pricediff))
            ELSE convert(varchar(max), convert(double precision, f.pricediff))
          END 
, loadshape = p.loadshape
, lstimeunit = ls.timeunit
, granularity = ls.granularity
, loadshapeHours = 'Hour Ending (HE) ' + CONVERT(VARCHAR,lsq.beghour + 1) + '00 through HE ' + CONVERT(VARCHAR, lsq.endhour) + '00 (' + CONVERT(VARCHAR, lsq.endhour-lsq.beghour-1) +' Hours each day), Monday Through Sunday, including NERC holidays; ' + tz.description
, loadshapeQuantity = convert(double precision, lsq.quantity)
, loadshapeQuantityLoadshape = lsq.loadshape
, loadshapeFlag = CASE
                    WHEN ls.loadshape is not null and ls.granularity = 'LOAD' and lsq.loadshape is null THEN 1
                    WHEN ls.loadshape is not null and ls.granularity = 'PROFILE' THEN 1
                    ELSE 0 END                      
FROM trade t
   INNER JOIN (SELECT *, CASE positiontype WHEN 'BUY' THEN 'PAY' WHEN 'SELL' THEN 'REC' END paystatus from position) p 
        on p.trade = t.trade
   INNER JOIN product pr on p.product = pr.product
   INNER JOIN powerposition pp on p.position = pp.position
   INNER JOIN powerquantity pq on pq.position = pp.position 
        AND pq.posdetail = pp.posdetail 
        AND pq.quantitystatus = 'TRADE'
   INNER JOIN blocktimezone btz on btz.block = p.block and t.timezone = btz.timezone
   LEFT OUTER JOIN fee f on f.dbvalue = p.position
        AND f.dbcolumn = 'POSITION'
        AND f.feemethod = 'COMMODITY PRICE'
        AND f.feemode in ('FIXED', 'VARIABLE')
        AND f.feetype IS NULL
   INNER JOIN counterparty co on co.counterparty = t.company    
   INNER JOIN counterparty cp on cp.counterparty = p.counterparty
   LEFT JOIN loadshape ls on ls.loadshape = p.loadshape
   LEFT JOIN loadshapequantity lsq on lsq.loadshape = ls.loadshape
   LEFT JOIN timezone tz on tz.timezone = t.timezone
 WHERE 1=1
 AND p.positionmode = 'PHYSICAL'
 AND t.collaboration = @collaboration 

您可以从第一行开始使用递归 CTE：

;WITH CTE AS (
        SELECT  TOP 1 *, 1 AS Id
        FROM    #t
        ORDER BY BegDate
        UNION ALL
        SELECT  t.*, c.Id + CASE WHEN t.quanitty = c.quanitty THEN 0 ELSE 1 END 
        FROM    CTE c
                JOIN #t t ON c.BegDate = DATEADD(MONTH, -1, t.BegDate)
    )
    SELECT  MIN(BegDate) AS BegDate, MAX(EndDate) AS EndDate, MIN(quanitty) AS quanitty
    FROM    CTE
    GROUP BY Id
    ORDER BY Id;

我像这样加载了示例数据：

SELECT  CAST(t.BegDate AS DATE) AS BegDate
        , CAST(t.EndDate AS DATE) AS EndDate
        , CAST(t.quanitty AS INT) AS quanitty
INTO    #t
FROM    (   VALUES 
            ('1/1/2014','1/31/2014',1),
            ('2/1/2014','2/28/2014',1),
            ('3/1/2014','3/31/2014',2),
            ('4/1/2014','4/30/2014',4),
            ('5/1/2014','5/31/2014',4),
            ('6/1/2014','6/30/2014',4),
            ('7/1/2014','7/31/2014',2),
            ('8/1/2014','8/30/2014',2)
        ) AS t(BegDate,EndDate,quanitty);