WideWorldImporters database catalog

THIS TOPIC APPLIES TO: yesSQL ServeryesAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse

The WideWorldImporters database contains all the transaction information and daily data for sales and purchases, as well as sensor data for vehicles and cold rooms.

Schemas

WideWorldImporters uses schemas for different purposes, such as storing data, defining how users can access the data, and providing objects for data warehouse development and integration.

Data schemas

These schemas contain the data. A number of tables are needed by all other schemas and are located in the Application schema.

Schema Description
Application Application-wide users, contacts, and parameters. This also contains reference tables with data that is used by multiple schemas
Purchasing Stock item purchases from suppliers and details about suppliers.
Sales Stock item sales to retail customers, and details about customers and sales people.
Warehouse Stock item inventory and transactions.

Secure-access schemas

These schemas are used for external applications that are not allowed to access the data tables directly. They contain views and stored procedures used by external applications.

Schema Description
Website All access to the database from the company website is through this schema.
Reports All access to the database from Reporting Services reports is through this schema.
PowerBI All access to the database from the Power BI dashboards via the Enterprise Gateway is through this schema.

Note that the Reports and PowerBI schemas are not used in the initial release of the sample database. However, all Reporting Services and Power BI samples built on top of this database are encouraged to use these schemas.

Development schemas

Special-purpose schemas

Schema Description
Integration Objects and procedures required for data warehouse integration (i.e. migrating the data to the WideWorldImportersDW database).
Sequences Holds sequences used by all tables in the application.

Tables

All tables in the database are in the data schemas.

Application Schema

Details of parameters and people (users and contacts), along with common reference tables (common to multiple other schemas).

Table Description
SystemParameters Contains system-wide configurable parameters.
People Contains user names, contact information, for all who use the application, and for the people that the Wide World Importers deals with at customer organizations. This includes staff, customers, suppliers, and any other contacts. For people who have been granted permission to use the system or website, the information includes login details.
Cities There are many addresses stored in the system, for people, customer organization delivery addresses, pickup addresses at suppliers, etc. Whenever an address is stored, there is a reference to a city in this table. There is also a spatial location for each city.
StateProvinces Cities are part of states or provinces. This table has details of those, including spatial data describing the boundaries each state or province.
Countries States or Provinces are part of countries. This table has details of those, including spatial data describing the boundaries of each country.
DeliveryMethods Choices for delivering stock items (e.g., truck/van, post, pickup, courier, etc.)
PaymentMethods Choices for making payments (e.g., cash, check, EFT, etc.)
TransactionTypes Types of customer, supplier, or stock transactions (e.g., invoice, credit note, etc.)

Purchasing Schema

Details of suppliers and of stock item purchases.

Table Description
Suppliers Main entity table for suppliers (organizations)
SupplierCategories Categories for suppliers (e.g., novelties, toys, clothing, packaging, etc.)
SupplierTransactions All financial transactions that are supplier-related (invoices, payments)
PurchaseOrders Details of supplier purchase orders
PurchaseOrderLines Detail lines from supplier purchase orders

Sales Schema

Details of customers, salespeople, and of stock item sales.

Table Description
Customers Main entity tables for customers (organizations or individuals)
CustomerCategories Categories for customers (ie novelty stores, supermarkets, etc.)
BuyingGroups Customer organizations can be part of groups that exert greater buying power
CustomerTransactions All financial transactions that are customer-related (invoices, payments)
SpecialDeals Special pricing. This can include fixed prices, discount in dollars or discount percent.
Orders Detail of customer orders
OrderLines Detail lines from customer orders
Invoices Details of customer invoices
InvoiceLines Detail lines from customer invoices

Warehouse Schema

Details of stock items, their holdings and transactions.

Table Description
StockItems Main entity table for stock items
StockItemHoldings Non-temporal columns for stock items. These are frequently updated columns.
StockGroups Groups for categorizing stock items (e.g., novelties, toys, edible novelties, etc.)
StockItemStockGroups Which stock items are in which stock groups (many to many)
Colors Stock items can (optionally) have colors
PackageTypes Ways that stock items can be packaged (e.g., box, carton, pallet, kg, etc.
StockItemTransactions Transactions covering all movements of all stock items (receipt, sale, write-off)
VehicleTemperatures Regularly recorded temperatures of vehicle chillers
ColdRoomTemperatures Regularly recorded temperatures of cold room chillers

Design considerations

Database design is subjective and there is no right or wrong way to design a database. The schemas and tables in this database show ideas for how you can design your own database.

Schema design

WideWorldImporters uses a small number of schemas so that it is easy to understand the database system and demonstrate database principles.

Wherever possible, the database collocates tables that are commonly queried together into the same schema to minimize join complexity.

The database schema has been code-generated based on a series of metadata tables in another database WWI_Preparation. This gives WideWorldImporters a very high degree of design consistency, naming consistency, and completeness. For details on how the schema has been generated see the source code: wide-world-importers/wwi-database-scripts

Table design

  • All tables have single column primary keys for join simplicity.
  • All schemas, tables, columns, indexes, and check constraints have a Description extended property that can be used to identify the purpose of the object or column. Memory-optimized tables are an exception to this since they don’t currently support extended properties.
  • All foreign keys are automatically indexed unless there is another non-clustered index that has the same left-hand component.
  • Auto-numbering in tables is based on sequences. These sequences are easier to work with across linked servers and similar environments than IDENTITY columns. Memory-optimized tables use IDENTITY columns since they don’t support in SQL Server 2016.
  • A single sequence (TransactionID) is used for these tables: CustomerTransactions, SupplierTransactions, and StockItemTransactions. This demonstrates how a set of tables can have a single sequence.
  • Some columns have appropriate default values.

Security schemas

For security, WideWorldImporters does not allow external applications to access data schemas directly. To isolate access, WideWorldImporters uses security-access schemas that do not hold data, but contain views and stored procedures. External applications use the security schemas to retrieve the data that they are allowed to view. This way, users can only run the views and stored procedures in the secure-access schemas

For example, this sample includes Power BI dashboards. An external application accesses these Power BI dashboards from the Power BI gateway as a user that has read-only permission on the PowerBI schema. For read-only permission, the user only needs SELECT and EXECUTE permission on the PowerBI schema. A database administrator at WWI assigns these permissions as needed.

Stored Procedures

Stored procedures are organized in schemas. Most of the schemas are used for configuration or sample purposes.

The Website schema contains the stored procedures that can be used by a Web front-end.

The Reports and PowerBI schemas are meant for reporting services and PowerBI purposes. Any extensions of the sample are encouraged to use these schemas for reporting purposes.

Website schema

These are the procedures used by a client application, such as a Web front-end.

Procedure Purpose
ActivateWebsiteLogon Allows a person (from Application.People) to have access to the website.
ChangePassword Changes a user’s password (for users that are not using external authentication mechanisms).
InsertCustomerOrders Allows inserting one or more customer orders (including the order lines).
InvoiceCustomerOrders Takes a list of orders to be invoiced and processes the invoices.
RecordColdRoomTemperatures Takes a sensor data list, as a table-valued parameter (TVP), and applies the data to the Warehouse.ColdRoomTemperatures temporal table.
RecordVehicleTemperature Takes a JSON array and uses it to update Warehouse.VehicleTemperatures.
SearchForCustomers Searches for customers by name or part of name (either the company name or the person name).
SearchForPeople Searches for people by name or part of name.
SearchForStockItems Searches for stock items by name or part of name or marketing comments.
SearchForStockItemsByTags Searches for stock items by tags.
SearchForSuppliers Searches for suppliers by name or part of name (either the company name or the person name).

Integration Schema

The stored procedures in this schema are used by the ETL process. They obtain the data needed from various tables for the timeframe required by the ETL package.

DataLoadSimulation Schema

Simulates a workload that inserts sales and purchases. The main stored procedure is PopulateDataToCurrentDate, which is used to insert sample data up to the current date.

Procedure Purpose
Configuration_ApplyDataLoadSimulationProcedures Recreates the procedures needed for data load simulation. This is needed for bringing data up to the current date.
Configuration_RemoveDataLoadSimulationProcedures This removes the procedures again after data simulation is complete.
DeactiveTemporalTablesBeforeDataLoad Removes the temporal nature of all temporal tables and where applicable, applies a trigger so that changes can be made as though they were being applied at an earlier date than the sys-temporal tables allow.
PopulateDataToCurrentDate Used to bring the data up to the current date. Should be run before any other configuration options after restoring the database from an initial backup.
ReactivateTemporalTablesAfterDataLoad Re-establishes the temporal tables, including checking for data consistency. (Removes the associated triggers).

Application Schema

These procedures are used to configure the sample. They are used to apply enterprise edition features to the standard edition version of the sample, and also to add auditing and full-text indexing.

Procedure Purpose
AddRoleMemberIfNonexistant Adds a member to a role if the member isn’t already in the role
Configuration_ApplyAuditing Adds auditing. Server auditing is applied for standard edition databases; additional database auditing is added for enterprise edition.
Configuration_ApplyColumnstoreIndexing Applies columnstore indexing to Sales.OrderLines and Sales.InvoiceLines and reindexes appropriately.
Configuration_ApplyFullTextIndexing Applies fulltext indexes to Application.People, Sales.Customers, Purchasing.Suppliers, and Warehouse.StockItems. Replaces Website.SearchForPeople, Website.SearchForSuppliers, Website.SearchForCustomers, Website.SearchForStockItems, Website.SearchForStockItemsByTags with replacement procedures that use fulltext indexing.
Configuration_ApplyPartitioning Applies table partitioning to Sales.CustomerTransactions andPurchasing.SupplierTransactions`, and rearranges the indexes to suit.
Configuration_ApplyRowLevelSecurity Applies row level security to filter customers by sales territory related roles.
Configuration_ConfigureForEnterpriseEdition Applies columnstore indexing, full text, in-memory, polybase, and partitioning.
Configuration_EnableInMemory Adds a memory-optimized filegroup (when not working in Azure), replaces Warehouse.ColdRoomTemperatures, Warehouse.VehicleTemperatures with in-memory equivalents, and migrates the data, recreates the Website.OrderIDList, Website.OrderList, Website.OrderLineList, Website.SensorDataList table types with memory-optimized equivalents, drops and recreates the procedures Website.InvoiceCustomerOrders, Website.InsertCustomerOrders, and Website.RecordColdRoomTemperatures that uses these table types.
Configuration_RemoveAuditing Removes the auditing configuration.
Configuration_RemoveRowLevelSecurity Removes the row level security configuration (this is needed for changes to the associated tables).
CreateRoleIfNonExistant Creates a database role if it doesn’t already exist.

Sequences Schema

Procedures to configure the sequences in the database.

Procedure Purpose
ReseedAllSequences Calls the procedure ReseedSequenceBeyondTableValue for all sequences.
ReseedSequenceBeyondTableValue Used to reposition the next sequence value beyond the value in any table that uses the same sequence. (Like a DBCC CHECKIDENT for identity columns equivalent for sequences but across potentially multiple tables).