Excel BI - PowerQuery Challenge 185

excel-challenges
power-query
For each group, generate the index. For same employee in a group, Index will remain same.
Published

March 24, 2026

Illustration for Excel BI - PowerQuery Challenge 185

Challenge Description

For each group, generate the index. For same employee in a group, Index will remain same.

Solutions

library(tidyverse)
library(readxl)

input = read_excel("Power Query/PQ_Challenge_185.xlsx", range = "A1:B13")
test  = read_excel("Power Query/PQ_Challenge_185.xlsx", range = "D1:F13")

result = input %>%
  mutate(Index = map_dbl(Emp, ~ which(unique(Emp) == .x)[1]), .by = Group)

all.equal(result, test)
# [1] TRUE

result2 = input %>%
mutate(Index = dense_rank(factor(Emp, levels = unique(Emp))), .by = Group) 

all.equal(result2, test)
# [1] TRUE

result3 = input %>%
mutate(Index = as.integer(factor(Emp, levels = unique(Emp))), .by = Group) 

all.equal(result3, test)
# [1] TRUE

  • Logic:

    • Reads the workbook range needed for the challenge

    • Builds helper columns that drive the final output

  • Strengths:

    • The R solution stays close to the workbook logic and keeps the transformation compact.

  • Areas for Improvement:

    • The code assumes the workbook layout and selected ranges remain stable.

  • Gem:

    • The best part of the solution is choosing the right intermediate shape before formatting the final output.
import pandas as pd
input = pd.read_excel("PQ_Challenge_185.xlsx", sheet_name="Sheet1", usecols="A:B")
test = pd.read_excel("PQ_Challenge_185.xlsx", sheet_name="Sheet1", usecols="D:F")
test.columns = test.columns.str.replace('.1', '')

input['Index'] = input.groupby('Group ')['Emp'].transform(lambda x: pd.factorize(x)[0]+1)

print(input.equals(test)) # True

  • Logic:

    • Reads the workbook range needed for the challenge

    • Aggregates or ranks values at the relevant grouping level

  • Strengths:

    • The Python version follows the same workbook rule in a direct pandas-oriented implementation.

  • Areas for Improvement:

    • As with the R version, any workbook layout change would require small adjustments.

  • Gem:

    • The implementation stays close to the source challenge instead of adding unnecessary abstraction.

Difficulty Level

This task is easy to moderate:

  • The transformation rule is readable, but the final layout still requires a careful implementation.