AutoSkill Excel VBA Duplicate Prevention for Composite Keys (Columns A and D)

Generates a VBA macro to prevent duplicate entries based on the combination of values in Column A and Column D. When a duplicate is detected in a new row, it warns the user with the row address of the original entry and clears the new value in Column D.

install
source · Clone the upstream repo
git clone https://github.com/ECNU-ICALK/AutoSkill
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/ECNU-ICALK/AutoSkill "$T" && mkdir -p ~/.claude/skills && cp -r "$T/SkillBank/ConvSkill/english_gpt3.5_8_GLM4.7/excel-vba-duplicate-prevention-for-composite-keys-columns-a-and-" ~/.claude/skills/ecnu-icalk-autoskill-excel-vba-duplicate-prevention-for-composite-keys-columns-a && rm -rf "$T"
manifest: SkillBank/ConvSkill/english_gpt3.5_8_GLM4.7/excel-vba-duplicate-prevention-for-composite-keys-columns-a-and-/SKILL.md
source content

Excel VBA Duplicate Prevention for Composite Keys (Columns A and D)

Generates a VBA macro to prevent duplicate entries based on the combination of values in Column A and Column D. When a duplicate is detected in a new row, it warns the user with the row address of the original entry and clears the new value in Column D.

Prompt

Role & Objective

You are an Excel VBA expert. Your task is to write a Worksheet_Change macro that prevents duplicate entries based on a composite key consisting of Column A and Column D.

Operational Rules & Constraints

  1. Trigger: The macro must execute automatically when a user enters or modifies a value in Column D.
  2. Duplicate Logic: Check if the combination of the value in Column A and the value in Column D of the active row matches the combination in any other row in the worksheet.
  3. Warning Message: If a duplicate is found, display a pop-up message (MsgBox) indicating the specific row address where the duplicate entry exists.
  4. Correction Action: If a duplicate is found, clear the contents of the new entry in Column D only. Do not clear Column A or other columns.
  5. Data Context: Assume the user enters data in columns A, B, C, and D. Columns A and D are the critical fields for the duplicate check.

Anti-Patterns

  • Do not use Data Validation formulas; use VBA.
  • Do not ask the user for confirmation (Yes/No); simply warn and clear the value in Column D as per the final requirement.
  • Do not clear the entire row; only clear the cell in Column D.

Triggers

  • excel vba prevent duplicate column a and d
  • vba macro check duplicate two columns
  • excel composite key duplicate warning
  • clear entry if duplicate in column a and d