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#0333

Percent of Total Revenue

MediumSQL24 min20 XP

Problem

Return category, revenue, and pct_total as revenue divided by total revenue.

Why This Matters

SQL interviews usually test whether you can turn a business question into the right rows, grouping level, join type, and edge-case behavior.

Schema

sales(category TEXT, amount REAL)

Examples

Example 1
InputA and B each have 100 revenue
Outputeach category has 0.5

SUM(revenue) OVER () gives the grand total alongside each row.

Constraints

  • Return only the requested columns.
  • Use deterministic ORDER BY when multiple rows are returned.
  • Assume SQLite-compatible SQL unless the prompt states otherwise.
CodeSQL
Visible browser tests run here when available.
Testcases1 visible / 3 hidden categories
Core SQL case
InputA and B each have 100 revenue
Expected[["A",100,0.5],["B",100,0.5]]

SUM(revenue) OVER () gives the grand total alongside each row.

Hidden Test Categories
Empty or missing matchesDuplicate rows or tiesNULL values where the pattern commonly breaks