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Data dictionary

As explained in 100 SQL Server Mistakes and How to Avoid Them

A data dictionary is a document describing data attributes, their meanings, rules, example values, types, dependencies, and lineage.

A data dictionary records what each attribute means before schema decisions turn assumptions into tables. It commonly lives in a spreadsheet and captures names, descriptions, business rules, example data, types, upstream dependencies, and lineage. section 4.1.3

Use it to make each attribute answer practical questions:

  • What does this value mean, and which business rules constrain expected values or uniqueness? section 4.1.3
  • What type and example value should represent it? section 4.1.3
  • Where did it originate, and through which dependencies did it reach this table? section 4.1.3

Tracking a marketing cookie ID

Record lineage as a path: Tracking ID in an impressions CSV from a cookie provider becomes TrackingID in staging, then CookieID in the marketing schema. This makes a stored value traceable instead of mysterious. section 4.1.3

Sales
Sales Order Date
Sales Order Number
Sales Person Name
Sales Person Email
Sales Area Name
Sales Area Manager
Customer Company Name
Customer Contact Name
Customer Contact Email
Customer Invoice Address
Customer Delivery Addresses
Sales Order Delivery Due Date
Sales Order Delivery Actual Date
Sales Order Item
Sales Order Quantities
Currier Used for Delivery
 
Purchasing
Supplier Name
Supplier Contact Name
Supplier Contact Email
Supplier Address
Purchase Order Date
Purchase Order Number
Purchase Order Items
Purchase Order Quantities
 
Products
Product Name
Product Stock Level
Product Next Manufacture Date
Product Next Manufacture Quantity
Back Order Manufacturing ID
Product Type Name
Product Type Description
Product Category Name
Product Category Description
Product Subcategory Name
Product Subcategory Description

Use this unnormalized Sales, Purchasing, and Products attribute list as a starting inventory for dictionary entries before normalization. section 4.1.3

How 100 SQL Server Mistakes and How to Avoid Them covers it

How deep it goes
Lists dictionary fields and illustrates lineage, without prescribing a fixed template or tool.
Examples
Traces a cookie identifier from an impressions CSV through staging into a marketing schema.
What it assumes
Assumes access to business analysts or application owners for attribute meanings and rules.
What you can do after
Build it from scratch in a spreadsheet by recording attribute metadata and lineage.
How it connects
Connects normalization with business rules, data types, upstream dependencies, and data lineage.

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This explainer was generated by Manning's knowledge graph from the text of 100 SQL Server Mistakes and How to Avoid Them. The section links point to the parts of the book it draws on.