过去几天我一直在研究这个问题并且正在进行.
我的问题是基于我在这篇文章中接受的答案:stackoverflow question
我现在将我的数据从单个400列表移动到更加可管理的数据库结构,非常感谢Damir Sudarevic.
我的数据库看起来像这样:
- CREATE TABLE JobFiles (
- JobID UNIQUEIDENTIFIER PRIMARY KEY,MachineID UNIQUEIDENTIFIER REFERENCES Machines(MachineID),[Desc] NVARCHAR(MAX),Name NVARCHAR(255),JobOpen BIT,[CreateDate] DATETIME NOT NULL DEFAULT GETDATE(),[ModifyDate] DATETIME NOT NULL DEFAULT GETDATE(),[CreatedByUser] NVARCHAR(64) DEFAULT '',[ModifiedByUser] NVARCHAR(64) DEFAULT '')
- GO
- CREATE TABLE JobParamType (
- ParamTypeID UNIQUEIDENTIFIER PRIMARY KEY,IsTrait NVARCHAR)
- GO
- CREATE TABLE JobParamGroup (
- ParamGroupID UNIQUEIDENTIFIER PRIMARY KEY,[Desc] NVARCHAR(MAX))
- GO
- CREATE TABLE JobParams (
- ParamID UNIQUEIDENTIFIER PRIMARY KEY,ParamTypeID UNIQUEIDENTIFIER REFERENCES JobParamType(ParamTypeID),ParamGroupID UNIQUEIDENTIFIER REFERENCES JobParamGroup(ParamGroupID),JobFileID UNIQUEIDENTIFIER REFERENCES JobFiles(JobID),IsEnabled BIT)
- GO
- -- Text based property
- CREATE TABLE JobTrait (
- ParamID UNIQUEIDENTIFIER PRIMARY KEY REFERENCES JobParams(ParamID),Value NVARCHAR(MAX) )
- GO
- -- Numeric based property
- CREATE TABLE JobMeasurement (
- ParamID UNIQUEIDENTIFIER PRIMARY KEY REFERENCES JobParams(ParamID),Value FLOAT,Format NVARCHAR(20),Unit NVARCHAR(MAX) )
- GO
但是,对于我的应用程序的特定功能,我需要将每个JobParamType.Name行列为包含JobMeasurement.Value或JobTrait.Value的列作为每个JobFiles.Name的数据.
JobParamType.IsTrait用于确定值是否为Measurement或Trait.
即
- JobName | ParamName1 | ParamName2 | ParamName3 ... | ParamName400
- "MyJob" MesurementValue TraitValue MesurementValue ... TraitValue
- "TestJob" MesurementValue TraitValue MesurementValue ... TraitValue
- "Job2" MesurementValue TraitValue MesurementValue ... TraitValue
- etc
我一直在使用数据透视表,并设法通过查看示例并跟随它们来获取JobParamType表中的列,但它现在变得非常复杂,因为我的数据在几个表之间分开,它开始让我的头受伤! !
- DECLARE @cols NVARCHAR(MAX)
- SELECT @cols = STUFF(( SELECT DISTINCT TOP 10 PERCENT
- '],[' + tParams.Name
- FROM dbo.JobParamType AS tParams
- ORDER BY '],[' + tParams.Name
- FOR XML PATH('')
- ),1,2,'') + ']'
- print @cols
我希望有人可以帮我转动并从多个表中获取数据.
我希望这是有道理的,我期待着你的帮助和讨论.
先谢谢你.
解决方法
我将在
this model发布一些例子 – 因为我已经有了它们.两种型号都非常相似,因此采用这种技术不会太麻烦.
当谈到头痛时,我发现最简单的方法是逐步进行,然后进行优化.
步骤1.
创建视图以展平模型; (see the model)
- CREATE VIEW dbo.vProperties AS
- SELECT m.MachineID AS [Machine ID],s.SetupID AS [Setup ID],p.PropertyID AS [Property ID],t.PropertyTypeID AS [Property Type ID],m.Name AS [Machine Name],s.Name AS [Setup Name],t.Name AS [Property Type Name],t.IsTrait AS [Is Trait],x.Value AS [Measurement Value],x.Unit AS [Unit],y.Value AS [Trait]
- FROM dbo.Machine AS m
- JOIN dbo.Setup AS s ON s.MachineID = m.MachineID
- JOIN dbo.Property AS p ON p.SetupID = s.SetupID
- JOIN dbo.PropertyType AS t ON t.PropertyTypeID = p.PropertyTypeID
- LEFT JOIN dbo.Measurement AS x ON x.PropertyID = p.PropertyID
- LEFT JOIN dbo.Trait AS y ON y.PropertyID = p.PropertyID
第2步.
创建一个视图,仅生成[设置名称],[属性类型名称],[值];请注意,在此测量值和特征最终在同一列中.您可能会使用JobName,ParameterTypeName,Value
- CREATE VIEW dbo.vSetupValues AS
- SELECT [Setup Name],[Property Type Name],COALESCE(cast([Measurement Value] AS varchar(50)),[Trait]) AS [Val]
- FROM dbo.vProperties
第3步.
使用要排序的列创建属性列表(参数)
- DECLARE @Props TABLE (
- id int IDENTITY (1,1),PropName varchar(50)
- );
- INSERT INTO @Props (PropName)
- SELECT DISTINCT [Name]
- FROM dbo.PropertyType
步骤4.
现在我将动态创建查询文本
- DECLARE @qw TABLE(
- id int IDENTITY (1,txt nchar(500)
- )
- INSERT INTO @qw (txt)
- SELECT 'SELECT' UNION
- SELECT '[Setup Name]' ;
- INSERT INTO @qw (txt)
- SELECT ',MAX(CASE [Property Type Name] WHEN ''' + PropName
- + ''' THEN Val ELSE NULL END) AS [' + PropName + ']'
- FROM @Props
- ORDER BY id;
- INSERT INTO @qw (txt)
- SELECT 'FROM dbo.vSetupValues' UNION
- SELECT 'GROUP BY [Setup Name]' UNION
- SELECT 'ORDER BY [Setup Name]';
第5步.
这里是查询的文本,从这一点开始我可以将它打包成一个存储过程,另一个视图,或者变成一个用作动态sql的变量.
- SELECT txt FROM @qw
回报
- SELECT
- [Setup Name],MAX(CASE [Property Type Name] WHEN 'Diameter LSL' THEN [Val] ELSE NULL END) AS [Diameter LSL],MAX(CASE [Property Type Name] WHEN 'Diameter USL' THEN [Val] ELSE NULL END) AS [Diameter USL],MAX(CASE [Property Type Name] WHEN 'Force LSL' THEN [Val] ELSE NULL END) AS [Force LSL],MAX(CASE [Property Type Name] WHEN 'Force USL' THEN [Val] ELSE NULL END) AS [Force USL],MAX(CASE [Property Type Name] WHEN 'Leak LSL' THEN [Val] ELSE NULL END) AS [Leak LSL],MAX(CASE [Property Type Name] WHEN 'Leak USL' THEN [Val] ELSE NULL END) AS [Leak USL],MAX(CASE [Property Type Name] WHEN 'Press Travel LSL' THEN [Val] ELSE NULL END) AS [Press Travel LSL],MAX(CASE [Property Type Name] WHEN 'Press Travel USL' THEN [Val] ELSE NULL END) AS [Press Travel USL],MAX(CASE [Property Type Name] WHEN 'Seal Height LSL' THEN [Val] ELSE NULL END) AS [Seal Height LSL],MAX(CASE [Property Type Name] WHEN 'Seal Height USL' THEN [Val] ELSE NULL END) AS [Seal Height USL]
- FROM dbo.vSetupValues
- GROUP BY [Setup Name]
- ORDER BY [Setup Name]
如果我运行这个:
alt text http://www.damirsystems.com/dp_images/machinesetup_results.png