I’ve had these notes laying around for a while, so, I thought I consolidate them here.   So, here are few guidelines to ensure the quality of your dimension table structures.

Dimension Table Effective Practices

• The table naming convention should identify it as a dimension table. For example:
  • Suffix Pattern:
    • <<TableName>>_Dim
    • <<TableName>>_D
  • Prefix Pattern:
    • Dim_<TableName>>
    • D_<TableName>>
• Have Primary Key (PK) assigned on table surrogate Key
• Audit fields – Type 1 dimensions should:
  • Have a Created Date timestamp – When the record was initially created
  • have a Last Update Timestamp – When was the record last updated
• Job Flow: Do not place the dimension processing in the fact jobs.
• Every Dimension should have a Zero (0), Unknown, row
• Fields should be ‘NOT NULL’ replacing nulls with a zero (0) numeric and integer type fields or space ( ‘ ‘ ) for Character type files.
• Keep dimension processing outside of the fact jobs

Related References

• Data Modeling – What is Data Modeling?
• Where do data models fit in the Software Development Life Cycle (SDLC) Process?
• What is a Common Data Model (CDM)?
• Data Modeling – The Value of Data Indicator Flags
• Data Modeling – What is Data Modeling?
• Data Modeling – Fact Table Effective Practices
• SQL Server – Basic SQL Server Object Naming Convention Guidance
• What are the Factor Affecting the Selection of Data Warehouse Naming Convention?
• Database Table Field Ordering Effective Practices