You have a data set that builds a union between two tables. You need to extract the data set. What should you use to extract the data set?

Question

Options

• Aphysical tables that use a single table extract
• Bphysical tables that use multiple table extracts
• Clogical tables that use a single table extract
• Dlogical tables that use multiple table extracts

• A
  12% (3)
• B
  68% (17)
• C
  4% (1)
• D
  16% (4)

Explanation

When a data source uses a union, the union is constructed at the physical table level in Tableau's data model - meaning rows from multiple base tables are stacked together before any logical relationships are applied. To properly extract this structure, you must use physical tables with multiple table extracts (B), which preserves each individual physical table in the .hyper file and maintains the union's row-combination logic.

Why the others are wrong:

• A (physical tables, single table extract): A single table extract flattens everything into one denormalized table, which breaks or ignores the union structure across multiple physical tables.
• C (logical tables, single table extract): Logical tables operate at the relationship layer above the union; using them with a single table extract bypasses the physical union entirely.
• D (logical tables, multiple table extracts): Logical tables still don't reach down to where the union lives - the physical layer - so even multiple logical table extracts won't correctly capture the union.

Memory tip: Think "Union = Physical + Multiple." A union physically stacks rows from more than one table, so you need physical tables and multiple table extracts - the answer mirrors the nature of the operation itself.

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