7

Enrollment_Changesテーブルにリストされている電話モデルは、加入者がその日に変更した電話です。

Enrollment_Changesにその後の変更がない場合、加入者が変更した電話はP_Enrollmentテーブルに一覧表示されます。

たとえば、加入者12345678は2011年1月5日にRAZRに登録しました。2011年11月1日に、彼はRAZRから変更しました。2012年5月19日のEnrollment_Changesで、彼が次のトランザクションで何を変更したかを確認できます。

iPhone 3に最初に登録した登録者の数をどのように見つけますか？

これが私がテーブルを作成するために持っているコードです

テーブルの作成：TBL 1

USE [Test2]
GO

/****** Object:  Table [dbo].[P_ENROLLMENT]    ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[P_ENROLLMENT](
    [Subid ] [float] NULL,
    [Enrollment_Date] [datetime] NULL,
    [Channel] [nvarchar](255) NULL,
    [Region] [nvarchar](255) NULL,
    [Active_Status] [float] NULL,
    [Drop_Date] [datetime] NULL,
    [Phone_Model] [nvarchar](255) NULL
) ON [PRIMARY]

GO

TBL 2

USE [Test2]
GO

/****** Object:  Table [dbo].[ENROLLMENT_CHANGES]     ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[ENROLLMENT_CHANGES](
    [Subid] [float] NULL,
    [Cdate] [datetime] NULL,
    [Phone_Model] [nvarchar](255) NULL
) ON [PRIMARY]

GO

TBL1を挿入します

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12345678, '2011-01-05 00:00:00', 'Retail', 'Southeast', 1, NULL, 'iPhone 4');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12346178, '2011-03-13 00:00:00', 'Indirect Dealers', 'West', 1, NULL, 'HTC Hero');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12346679, '2011-05-19 00:00:00', 'Indirect Dealers', 'Southeast', 0, '2012-03-15 00:00:00', 'Droid 2');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12347190, '2011-07-25 00:00:00', 'Retail', 'Northeast', 0, '2012-05-21 00:00:00', 'iPhone 4');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12347701, '2011-08-14 00:00:00', 'Indirect Dealers', 'West', 1, NULL, 'HTC Hero');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12348212, '2011-09-30 00:00:00', 'Retail', 'West', 1, NULL, 'Droid 2');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12348723, '2011-10-20 00:00:00', 'Retail', 'Southeast', 1, NULL, 'Southeast');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12349234, '2012-01-06 00:00:00', 'Indirect Dealers', 'West', 0, '2012-02-14 00:00:00', 'West');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12349745, '2012-01-26 00:00:00', 'Retail', 'Northeast', 0, '2012-04-15 00:00:00', 'HTC Hero');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12350256, '2012-02-11 00:00:00', 'Retail', 'Southeast', 1, NULL, 'iPhone 4');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12350767, '2012-03-02 00:00:00', 'Indirect Dealers', 'West', 1, NULL, 'Sidekick');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12351278, '2012-04-18 00:00:00', 'Retail', 'Midwest', 1, NULL, 'iPhone 3');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12351789, '2012-05-08 00:00:00', 'Indirect Dealers', 'West', 0, '2012-07-04 00:00:00', 'iPhone 3');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12352300, '2012-06-24 00:00:00', 'Retail', 'Midwest', 1, NULL, 'Droid 2');

INSERT INTO [P_ENROLLMENT]([Subid ], [Enrollment_Date], [Channel], [Region], [Active_Status], [Drop_Date], [Phone_Model]) 
    VALUES(12352811, '2012-06-25 00:00:00', 'Retail', 'Southeast', 1, NULL, 'Sidekick');

TBL2を挿入します

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12345678, '2011-11-01 00:00:00', 'RAZR');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12346178, '2012-01-07 00:00:00', 'HTC Hero');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12348723, '2012-01-28 00:00:00', 'RAZR');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12350256, '2012-02-21 00:00:00', 'Blackberry Bold');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12349745, '2012-05-05 00:00:00', 'HTC Hero');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12345678, '2012-05-19 00:00:00', 'Palm Pre');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12347190, '2012-05-20 00:00:00', 'HTC Hero');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12350256, '2012-05-21 00:00:00', 'Blackberry Bold');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12349234, '2012-06-04 00:00:00', 'Palm Pre');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12346178, '2012-06-05 00:00:00', 'iPhone 3');

INSERT INTO [ENROLLMENT_CHANGES]([Subid], [Cdate], [Phone_Model]) 
    VALUES(12350767, '2012-06-10 00:00:00', 'iPhone 3');
4

3 に答える 3

4

カウントのために

select COUNT(*) Total
from
(
    select e.*,
        rn = row_number() over (partition by e.subid order by c.cdate desc),
        first_model = coalesce(c.phone_model, e.phone_model)
    from [P_ENROLLMENT] e
    left join [ENROLLMENT_CHANGES] c on c.subid = e.subid
) x
where rn=1 and first_model = 'iPhone 3'

すべての記録について

select *
from
(
    select e.*,
        rn = row_number() over (partition by e.subid order by c.cdate desc),
        first_model = coalesce(c.phone_model, e.phone_model)
    from [P_ENROLLMENT] e
    left join [ENROLLMENT_CHANGES] c on c.subid = e.subid
) x
where rn=1 and first_model = 'iPhone 3'
order by subid
于 2012-10-01T00:43:46.930 に答える
1

テーブルの最初のレコードがiPhone3であるかどうかを知りたいとします。次のようなものです。

select count(*)
from (select e.*,
             row_number() over (partition by subid order by enrollment_date) as seqnum
      from p_enrollment e
     ) e
where seqnum = 1 and phone_model = 'iPhone 3'
于 2012-10-01T00:31:34.953 に答える
1

おそらく私はあまりにも単純に考えていますが、次のどちらもあなたが探していることをしませんか？：

SELECT      Phone_Model
            , COUNT(*) AS Initially_Enrolled
FROM        p_enrollment
GROUP BY    Phone_Model

（SQLFiddleの動作：http ：//sqlfiddle.com/#！3/68258/4 ）

また

SELECT      COUNT(*) AS Initially_Enrolled
FROM        p_enrollment
WHERE       Phone_Model = 'iPhone 3'

（SQLFiddleの動作：http ：//sqlfiddle.com/#！3/68258/3 ）

最初の登録のみが必要なため、ENROLLMENT_CHANGESテーブルは関係ありません。

于 2012-10-01T01:00:48.280 に答える