我正在尝试以下查询,
DECLARE @EntityType varchar(25)
SET @EntityType = 'Accessory';
WITH Entities (
E_ID, E_Type,
P_ID, P_Name, P_DataType, P_Required, P_OnlyOne,
PV_ID, PV_Value, PV_EntityID, PV_ValueEntityID,
PV_UnitValueID, PV_UnitID, PV_UnitName, PV_UnitDesc, PV_MeasureID, PV_MeasureName, PV_UnitValue,
PV_SelectionID, PV_DropDownID, PV_DropDownName, PV_DropDownOptionID, PV_DropDownOptionName, PV_DropDownOptionDesc,
RecursiveLevel
)
AS
(
-- Original Query
SELECT dbo.Entity.ID AS E_ID, dbo.EntityType.Name AS E_Type,
dbo.Property.ID AS P_ID, dbo.Property.Name AS P_Name, DataType.Name AS P_DataType, Required AS P_Required, OnlyOne AS P_OnlyOne,
dbo.PropertyValue.ID AS PV_ID, dbo.PropertyValue.Value AS PV_Value, dbo.PropertyValue.EntityID AS PV_EntityID, dbo.PropertyValue.ValueEntityID AS PV_ValueEntityID,
dbo.UnitValue.ID AS PV_UnitValueID, dbo.UnitOfMeasure.ID AS PV_UnitID, dbo.UnitOfMeasure.Name AS PV_UnitName, dbo.UnitOfMeasure.Description AS PV_UnitDesc, dbo.Measure.ID AS PV_MeasureID, dbo.Measure.Name AS PV_MeasureName, dbo.UnitValue.UnitValue AS PV_UnitValue,
dbo.DropDownSelection.ID AS PV_SelectionID, dbo.DropDown.ID AS PV_DropDownID, dbo.DropDown.Name AS PV_DropDownName, dbo.DropDownOption.ID AS PV_DropDownOptionID, dbo.DropDownOption.Name AS PV_DropDownOptionName, dbo.DropDownOption.Description AS PV_DropDownOptionDesc,
0 AS RecursiveLevel
FROM dbo.Entity
INNER JOIN dbo.EntityType ON dbo.EntityType.ID = dbo.Entity.TypeID
INNER JOIN dbo.Property ON dbo.Property.EntityTypeID = dbo.Entity.TypeID
INNER JOIN dbo.PropertyValue ON dbo.Property.ID = dbo.PropertyValue.PropertyID AND dbo.PropertyValue.EntityID = dbo.Entity.ID
INNER JOIN dbo.DataType ON dbo.DataType.ID = dbo.Property.DataTypeID
LEFT JOIN dbo.UnitValue ON dbo.UnitValue.ID = dbo.PropertyValue.UnitValueID
LEFT JOIN dbo.UnitOfMeasure ON dbo.UnitOfMeasure.ID = dbo.UnitValue.UnitOfMeasureID
LEFT JOIN dbo.Measure ON dbo.Measure.ID = dbo.UnitOfMeasure.MeasureID
LEFT JOIN dbo.DropDownSelection ON dbo.DropDownSelection.ID = dbo.PropertyValue.DropDownSelectedID
LEFT JOIN dbo.DropDownOption ON dbo.DropDownOption.ID = dbo.DropDownSelection.SelectedOptionID
LEFT JOIN dbo.DropDown ON dbo.DropDown.ID = dbo.DropDownSelection.DropDownID
WHERE dbo.EntityType.Name = @EntityType
UNION ALL
-- Recursive Query?
SELECT E2.E_ID AS E_ID, dbo.EntityType.Name AS E_Type,
dbo.Property.ID AS P_ID, dbo.Property.Name AS P_Name, DataType.Name AS P_DataType, Required AS P_Required, OnlyOne AS P_OnlyOne,
dbo.PropertyValue.ID AS PV_ID, dbo.PropertyValue.Value AS PV_Value, dbo.PropertyValue.EntityID AS PV_EntityID, dbo.PropertyValue.ValueEntityID AS PV_ValueEntityID,
dbo.UnitValue.ID AS PV_UnitValueID, dbo.UnitOfMeasure.ID AS PV_UnitID, dbo.UnitOfMeasure.Name AS PV_UnitName, dbo.UnitOfMeasure.Description AS PV_UnitDesc, dbo.Measure.ID AS PV_MeasureID, dbo.Measure.Name AS PV_MeasureName, dbo.UnitValue.UnitValue AS PV_UnitValue,
dbo.DropDownSelection.ID AS PV_SelectionID, dbo.DropDown.ID AS PV_DropDownID, dbo.DropDown.Name AS PV_DropDownName, dbo.DropDownOption.ID AS PV_DropDownOptionID, dbo.DropDownOption.Name AS PV_DropDownOptionName, dbo.DropDownOption.Description AS PV_DropDownOptionDesc,
(RecursiveLevel + 1)
FROM Entities AS E2
INNER JOIN dbo.Entity ON dbo.Entity.ID = E2.PV_ValueEntityID
INNER JOIN dbo.EntityType ON dbo.EntityType.ID = dbo.Entity.TypeID
INNER JOIN dbo.Property ON dbo.Property.EntityTypeID = dbo.Entity.TypeID
INNER JOIN dbo.PropertyValue ON dbo.Property.ID = dbo.PropertyValue.PropertyID AND dbo.PropertyValue.EntityID = E2.E_ID
INNER JOIN dbo.DataType ON dbo.DataType.ID = dbo.Property.DataTypeID
INNER JOIN dbo.UnitValue ON dbo.UnitValue.ID = dbo.PropertyValue.UnitValueID
INNER JOIN dbo.UnitOfMeasure ON dbo.UnitOfMeasure.ID = dbo.UnitValue.UnitOfMeasureID
INNER JOIN dbo.Measure ON dbo.Measure.ID = dbo.UnitOfMeasure.MeasureID
INNER JOIN dbo.DropDownSelection ON dbo.DropDownSelection.ID = dbo.PropertyValue.DropDownSelectedID
INNER JOIN dbo.DropDownOption ON dbo.DropDownOption.ID = dbo.DropDownSelection.SelectedOptionID
INNER JOIN dbo.DropDown ON dbo.DropDown.ID = dbo.DropDownSelection.DropDownID
)
SELECT E_ID, E_Type,
P_ID, P_Name, P_DataType, P_Required, P_OnlyOne,
PV_ID, PV_Value, PV_EntityID, PV_ValueEntityID,
PV_UnitValueID, PV_UnitID, PV_UnitName, PV_UnitDesc, PV_MeasureID, PV_MeasureName, PV_UnitValue,
PV_SelectionID, PV_DropDownID, PV_DropDownName, PV_DropDownOptionID, PV_DropDownOptionName, PV_DropDownOptionDesc,
RecursiveLevel
FROM Entities
INNER JOIN [dbo].[Entity] AS dE
ON dE.ID = PV_EntityID
问题是第二个查询,“递归查询”正在获取我期望的数据,因为我不能像第一个查询那样做 LEFT JOIN。(至少在我看来)。
如果我删除了需要 LEFT(外部)JOIN 的数据的获取,那么递归就可以完美地工作。我的问题是我两者都需要。有没有办法我可以做到这一点?