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POHow to get set-based solution for a difficult join
 

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  1. POHow to get set-based solution for a difficult join
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    <p>I've got a Table with a list of Products.<br> I've got a Table with a list of Merchants.<br> I've got a Table with a list of Warehouses. </p> <p>I've got a WarehouseMerchant Table so a a warehouse can have many merchants assigned. </p> <p>I've got a WarehouseMerchantProduct Table so a merchant can have its products listed in a warehouse</p> <p>I've got a Merchant Link Table which can link 2 merchants</p> <pre><code>MerchantLinkID int MasterMerchantID int LinkedMerchantID int PreferenceOrder int </code></pre> <p>What i need to do is pass in a product ID and get a unique list of merchants products who can sell it.</p> <p>4 Rules</p> <ol> <li>If the merchant has a linked merchant who also sells the product, then don't show the linked merchants product</li> <li>If the merchant has a linked merchant who also sells the product, but the master merchants stock level is 0, then only show the linked merchants product</li> <li>In the event that a merchant has stock in multiple warehouses, then there is a preference order in the warehouseMerchant Table to select which one to use</li> <li>There should only be one product per merchant after this has all ran</li> </ol> <p>I've been racking my brains trying to figure out a solution. I was going down the route of cursors, but it was getting a bit unwieldy. Then i was given the 4 rules as a requirement which sent me back to the drawing board. </p> <p>If anyone can think of a quick and easy(ish) set-based solution for this then I'd love to hear it.</p> <p>Here is the script to create the tables and relationships</p> <pre><code> CREATE TABLE [dbo].[MW_Merchant]( [MerchantID] [int] IDENTITY(1,1) NOT NULL, [MerchantName] [nvarchar](150) NOT NULL, [MerchantCode] [char](10) NOT NULL, [Active] [bit] NOT NULL, CONSTRAINT [PK_Merchant] PRIMARY KEY CLUSTERED ( [MerchantID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY], CONSTRAINT [ucMerchantCode] UNIQUE NONCLUSTERED ( [MerchantCode] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO /****** Object: Table [dbo].[MW_Warehouse] Script Date: 04/30/2013 09:17:39 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_PADDING ON GO CREATE TABLE [dbo].[MW_Warehouse]( [WarehouseID] [int] IDENTITY(1,1) NOT NULL, [WarehouseName] [nvarchar](150) NOT NULL, [WarehouseCode] [varchar](10) NOT NULL, [Active] [bit] NOT NULL, CONSTRAINT [PK_Warehouse] PRIMARY KEY CLUSTERED ( [WarehouseID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO /****** Object: Table [dbo].[MW_WarehouseMerchantProduct] Script Date: 04/30/2013 09:17:39 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_PADDING ON GO CREATE TABLE [dbo].[MW_WarehouseMerchantProduct]( [WarehouseMerchantProductID] [int] IDENTITY(1,1) NOT NULL, [WarehouseID] [int] NOT NULL, [MerchantID] [int] NOT NULL, [ProductCode] [varchar](30) NOT NULL, [StockLevel] [int] NOT NULL, [Active] [bit] NOT NULL, [PriorityOrder] [int] NOT NULL, CONSTRAINT [PK_MW_WarehouseProduct] PRIMARY KEY CLUSTERED ( [WarehouseMerchantProductID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO SET ANSI_PADDING OFF GO /****** Object: Table [dbo].[MW_WarehouseMerchant] Script Date: 04/30/2013 09:17:39 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[MW_WarehouseMerchant]( [WarehouseMerchantID] [int] IDENTITY(1,1) NOT NULL, [WarehouseID] [int] NOT NULL, [MerchantID] [int] NOT NULL, [Active] [bit] NOT NULL, [PreferenceOrder] [int] NOT NULL, CONSTRAINT [PK_MW_WarehouseMerchant] PRIMARY KEY CLUSTERED ( [WarehouseMerchantID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO /****** Object: Table [dbo].[MW_MerchantLink] Script Date: 04/30/2013 09:17:39 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[MW_MerchantLink]( [MerchantLinkID] [int] IDENTITY(1,1) NOT NULL, [MasterMerchantID] [int] NOT NULL, [LinkedMerchantID] [int] NOT NULL, [PreferenceOrder] [int] NOT NULL, CONSTRAINT [PK_MW_MerchantLink] PRIMARY KEY CLUSTERED ( [MerchantLinkID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO /****** Object: Default [DF_MW_WarehouseMerchant_PreferenceOrder] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchant] ADD CONSTRAINT [DF_MW_WarehouseMerchant_PreferenceOrder] DEFAULT ((10)) FOR [PreferenceOrder] GO /****** Object: Default [DF_MW_WarehouseMerchantProduct_PriorityOrder] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchantProduct] ADD CONSTRAINT [DF_MW_WarehouseMerchantProduct_PriorityOrder] DEFAULT ((10)) FOR [PriorityOrder] GO /****** Object: ForeignKey [FK_MW_MerchantLink_MW_Merchant] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_MerchantLink] WITH CHECK ADD CONSTRAINT [FK_MW_MerchantLink_MW_Merchant] FOREIGN KEY([MasterMerchantID]) REFERENCES [dbo].[MW_Merchant] ([MerchantID]) GO ALTER TABLE [dbo].[MW_MerchantLink] CHECK CONSTRAINT [FK_MW_MerchantLink_MW_Merchant] GO /****** Object: ForeignKey [FK_MW_MerchantLink_MW_Merchant1] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_MerchantLink] WITH CHECK ADD CONSTRAINT [FK_MW_MerchantLink_MW_Merchant1] FOREIGN KEY([LinkedMerchantID]) REFERENCES [dbo].[MW_Merchant] ([MerchantID]) GO ALTER TABLE [dbo].[MW_MerchantLink] CHECK CONSTRAINT [FK_MW_MerchantLink_MW_Merchant1] GO /****** Object: ForeignKey [FK_MW_WarehouseMerchant_MW_Merchant] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchant] WITH CHECK ADD CONSTRAINT [FK_MW_WarehouseMerchant_MW_Merchant] FOREIGN KEY([MerchantID]) REFERENCES [dbo].[MW_Merchant] ([MerchantID]) GO ALTER TABLE [dbo].[MW_WarehouseMerchant] CHECK CONSTRAINT [FK_MW_WarehouseMerchant_MW_Merchant] GO /****** Object: ForeignKey [FK_MW_WarehouseMerchant_MW_Warehouse] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchant] WITH CHECK ADD CONSTRAINT [FK_MW_WarehouseMerchant_MW_Warehouse] FOREIGN KEY([WarehouseID]) REFERENCES [dbo].[MW_Warehouse] ([WarehouseID]) GO ALTER TABLE [dbo].[MW_WarehouseMerchant] CHECK CONSTRAINT [FK_MW_WarehouseMerchant_MW_Warehouse] GO /****** Object: ForeignKey [FK_MW_WarehouseMerchantProduct_MW_Merchant] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchantProduct] WITH CHECK ADD CONSTRAINT [FK_MW_WarehouseMerchantProduct_MW_Merchant] FOREIGN KEY([MerchantID]) REFERENCES [dbo].[MW_Merchant] ([MerchantID]) GO ALTER TABLE [dbo].[MW_WarehouseMerchantProduct] CHECK CONSTRAINT [FK_MW_WarehouseMerchantProduct_MW_Merchant] GO /****** Object: ForeignKey [FK_MW_WarehouseProduct_MW_Warehouse] Script Date: 04/30/2013 09:17:39 ******/ ALTER TABLE [dbo].[MW_WarehouseMerchantProduct] WITH CHECK ADD CONSTRAINT [FK_MW_WarehouseProduct_MW_Warehouse] FOREIGN KEY([WarehouseID]) REFERENCES [dbo].[MW_Warehouse] ([WarehouseID]) GO ALTER TABLE [dbo].[MW_WarehouseMerchantProduct] CHECK CONSTRAINT [FK_MW_WarehouseProduct_MW_Warehouse] GO </code></pre> <p>And some test data</p> <pre><code>/****** Object: Table [dbo].[MW_Merchant] Script Date: 04/30/2013 09:41:50 ******/ SET IDENTITY_INSERT [dbo].[MW_Merchant] ON INSERT [dbo].[MW_Merchant] ([MerchantID], [MerchantName], [MerchantCode], [Active]) VALUES (24, N'Merchant 1', N'MERCH1 ', 1) INSERT [dbo].[MW_Merchant] ([MerchantID], [MerchantName], [MerchantCode], [Active]) VALUES (27, N'Merchant 2', N'MERCH2 ', 1) INSERT [dbo].[MW_Merchant] ([MerchantID], [MerchantName], [MerchantCode], [Active]) VALUES (28, N'Merchant 3', N'MERCH3 ', 1) SET IDENTITY_INSERT [dbo].[MW_Merchant] OFF /****** Object: Table [dbo].[MW_Warehouse] Script Date: 04/30/2013 09:41:50 ******/ SET IDENTITY_INSERT [dbo].[MW_Warehouse] ON INSERT [dbo].[MW_Warehouse] ([WarehouseID], [WarehouseName], [WarehouseCode], [Active]) VALUES (12, N'Warehouse 1', N'WARE1', 1) INSERT [dbo].[MW_Warehouse] ([WarehouseID], [WarehouseName], [WarehouseCode], [Active]) VALUES (13, N'Warehouse 2', N'WARE2', 1) INSERT [dbo].[MW_Warehouse] ([WarehouseID], [WarehouseName], [WarehouseCode], [Active]) VALUES (14, N'Warehouse 3', N'WARE3', 1) SET IDENTITY_INSERT [dbo].[MW_Warehouse] OFF /****** Object: Table [dbo].[MW_WarehouseMerchantProduct] Script Date: 04/30/2013 09:41:50 ******/ SET IDENTITY_INSERT [dbo].[MW_WarehouseMerchantProduct] ON INSERT [dbo].[MW_WarehouseMerchantProduct] ([WarehouseMerchantProductID], [WarehouseID], [MerchantID], [ProductCode], [StockLevel], [Active], [PriorityOrder]) VALUES (93, 13, 24, N'TESTPRODUCT', 20, 1, 10) INSERT [dbo].[MW_WarehouseMerchantProduct] ([WarehouseMerchantProductID], [WarehouseID], [MerchantID], [ProductCode], [StockLevel], [Active], [PriorityOrder]) VALUES (96, 14, 24, N'TESTPRODUCT', 20, 1, 10) INSERT [dbo].[MW_WarehouseMerchantProduct] ([WarehouseMerchantProductID], [WarehouseID], [MerchantID], [ProductCode], [StockLevel], [Active], [PriorityOrder]) VALUES (97, 14, 27, N'TESTPRODUCT', 10, 1, 10) SET IDENTITY_INSERT [dbo].[MW_WarehouseMerchantProduct] OFF /****** Object: Table [dbo].[MW_MerchantLink] Script Date: 04/30/2013 09:41:50 ******/ SET IDENTITY_INSERT [dbo].[MW_MerchantLink] ON INSERT [dbo].[MW_MerchantLink] ([MerchantLinkID], [MasterMerchantID], [LinkedMerchantID], [PreferenceOrder]) VALUES (22, 24, 27, 1) INSERT [dbo].[MW_MerchantLink] ([MerchantLinkID], [MasterMerchantID], [LinkedMerchantID], [PreferenceOrder]) VALUES (23, 24, 28, 2) SET IDENTITY_INSERT [dbo].[MW_MerchantLink] OFF </code></pre> <p>In the example data, my returned row should be the WarehouseMerchantProductID 93 93,96 and 97 all have stock, however</p> <p>93 and 96 belong to the same merchant and should be selected based on PreferenceOrder in the WarehouseMerchant Table</p> <p>Merchant 27 is linked to 24 so shouldnt appear (unless 24 goes out of stock)</p>
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    1. PTQuestion
    1. USTonyRoberts
    1. USTonyRoberts
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    1. This table or related slice is empty.
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    1. PO
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      1. POHow to get set-based solution for a difficult join
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
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      1. POHow to get set-based solution for a difficult join
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThis is a new and interesting use of the number 2 that I've not previously encountered. (You say 2 rules twice, and then have 4 bullet points?)
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      1. POHow to get set-based solution for a difficult join
      1. USDamien_The_Unbeliever
    2. COoops...sorry...started off as 2, then i remembered important information (3 & 4) and forgot to update it.
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      1. POHow to get set-based solution for a difficult join
      1. USTonyRoberts
    3. COCan you post your create table statements along with some sample data to get us started? Most of us are lazy and can't be bothered to setup 6 tables just so that we can help you.
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      1. POHow to get set-based solution for a difficult join
      1. USColin 't Hart
 

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