DRAFT ETL+ Load Replace Example -- Keys & Indexes for Target Table, DW PK not on Source Field/Watermark
Examples of source data and the target tables that result from a Load Replace focusing on the keys and indexes created for the resulting target table created in the data warehouse.
For Excel and .csv file data sources designating a column as a DW PK on the Design page has no impact on the columns in the target table that are indexed.
Configurations
The ‘watermark’ field, ModifiedSequence, is also the DW PK (see Design page).
Data source in this example is a .csv file. Same results also reported to Excel file data sources.
The key column is designated.
The ModifiedSequence column represents a sequentially incremented value.
Initial Load
Source file
Target Table After
ETL+ Preview Table
Log: (5 rows loaded)
SSMS display. ModifiedSequence is given a index.
The designation of the key column in the Design page has no effect.
Related Pages
Unique/Primary Keys in Excel Tables
Notes on how to prevent, find, highlight, report and remove duplicate rows in Excel.