我期待创建一个视图,从两个表"Schedule"和"Reference"中提取数据.
Schedule有50多列(它几乎完全非规范化 - 不是我的设计),其中大部分都包含一个可以连接到Reference表中的列的值.
如何编写SQL语句以将Schedules中的每个列正确连接到Reference中的单个列?
Schedule表定义为:
CREATE TABLE [dbo].[Schedule](
[ID] [int] NOT NULL,
[SCHEDULEWEEK] [datetime] NOT NULL,
[EMPNO] [numeric](10, 0) NOT NULL,
[EMPLNAME] [varchar](32) NULL,
[EMPFNAME] [varchar](32) NULL,
[EMPSENDATE] [datetime] NULL,
[EMPHIREDATE] [datetime] NULL,
[EMPTYPE] [char](1) NULL,
[EMPSTATUS] [char](1) NULL,
[SNREFUSALS] [tinyint] NULL,
[QUALSTRING] [varchar](128) NULL,
[JOBOVERSHIFTTYPE] [bit] NULL,
[SHORTNOTICE] [bit] NULL,
[SHORTNOTICEWAP] [bit] NULL,
[SHORTNOTICEPHONE] [varchar](32) NULL,
[LEADHAND] [bit] NULL,
[DUALCURRENCY] [bit] NULL,
[MIN100WINDOW] [bit] NULL,
[STATHOLIDAY] [bit] NULL,
[AREAOVERHOURS] [bit] NULL,
[DOUBLEINTERZONES] [bit] NULL,
[MAXDAYSPERWEEK] [tinyint] NULL,
[MAXHOURSPERWEEK] [numeric](10, 2) NULL,
[MAXHOURSPERSHIFT] [numeric](10, 2) NULL,
[MAXDOUBLESPERWEEK] [tinyint] NULL,
[ASSIGNEDDAYS] [tinyint] NULL,
[ASSIGNEDHOURS] [numeric](10, 2) NULL,
[ASSIGNEDDOUBLES] [tinyint] NULL,
[ASSIGNEDLOAHOURS] [numeric](10, 2) NULL,
[SHIFTNO1] [int] NULL,
[TEXT1_1] [varchar](64) NULL,
[TEXT2_1] [varchar](64) NULL,
[DAYFLAG1] [bit] NULL,
[COMMENT1] [text] NULL,
[SHIFTNO2] [int] NULL,
[TEXT1_2] [varchar](64) NULL,
[TEXT2_2] [varchar](64) NULL,
[DAYFLAG2] [bit] NULL,
[COMMENT2] [text] NULL,
[SHIFTNO3] [int] NULL,
[TEXT1_3] [varchar](64) NULL,
[TEXT2_3] [varchar](64) NULL,
[DAYFLAG3] [bit] NULL,
[COMMENT3] [text] NULL,
[SHIFTNO4] [int] NULL,
[TEXT1_4] [varchar](64) NULL,
[TEXT2_4] [varchar](64) NULL,
[DAYFLAG4] [bit] NULL,
[COMMENT4] [text] NULL,
[SHIFTNO5] [int] NULL,
[TEXT1_5] [varchar](64) NULL,
[TEXT2_5] [varchar](64) NULL,
[DAYFLAG5] [bit] NULL,
[COMMENT5] [text] NULL,
[SHIFTNO6] [int] NULL,
[TEXT1_6] [varchar](64) NULL,
[TEXT2_6] [varchar](64) NULL,
[DAYFLAG6] [bit] NULL,
[COMMENT6] [text] NULL
-- Snip
) ON [PRIMARY]
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参考表定义为:
CREATE TABLE [dbo].[Reference](
[ID] [int] NOT NULL,
[CODE] [varchar](21) NOT NULL,
[LOCATIONCODE] [varchar](4) NOT NULL,
[SCHAREACODE] [varchar](16) NOT NULL,
[LOCATIONNAME] [varchar](32) NOT NULL,
[FLTAREACODE] [varchar](16) NOT NULL
) ON [PRIMARY]
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我正在尝试将Schedule中的每个[TEXT1_ ]/[TEXT2_ ]列加入参考中的[SCHAREACODE]列.所有参考表都包含员工可以工作的区域列表.
我认为他意味着多次加入Reference表:
SELECT *
FROM Schedule AS S
INNER JOIN Reference AS R1
ON R1.ID = S.FirstID
INNER JOIN Reference AS R2
ON R2.ID = S.SecondID
INNER JOIN Reference AS R3
ON R3.ID = S.ThirdID
INNER JOIN Reference AS R4
ON R4.ID = S.ForthID
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来自更新的问题
也许是这样的?无论你做什么都会很混乱。
SELECT S.ID
S.TEXT1_1,
TEXT1_1_RID = COALESCE((SELECT MAX(R.ID) FROM Reference R WHERE R.SCHAREACODE = S.TEXT1_1), 0),
S.TEXT1_2,
TEXT1_2_RID = COALESCE((SELECT MAX(R.ID) FROM Reference R WHERE R.SCHAREACODE = S.TEXT1_2), 0),
...
FROM Schedule S
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