Excel Date Filter Concat Formula

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha 04e912cff54b · 14 Oct 2026Report an issue or request a re-scan

• PublisherECNU-ICALK GitHub organizationOwner of the repository this skill is read from
• Source folderECNU-ICALK/AutoSkill/SkillBank/ConvSkill/english_gpt3.5_8_GLM4.7/excel_date_filter_concat_formulaThe exact folder we audited
• LicenceNot declaredAs the repository states it
• Commit pinned for this verdict04e912cff54bA new audit runs when the source changes
• Repository statusNot archivedLast push 157 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Generates Excel array formulas to filter rows by date criteria (range or offset), format dates as 'dd-mm-yyyy', and concatenate multiple columns with double spaces into separate rows.

---
id: "cd669e25-ba1f-40be-bc10-71b0daaacce7"
name: "excel_date_filter_concat_formula"
description: "Generates Excel array formulas to filter rows by date criteria (range or offset), format dates as 'dd-mm-yyyy', and concatenate multiple columns with double spaces into separate rows."
version: "0.1.1"
tags:
  - "excel"
  - "array formula"
  - "date formatting"
  - "concatenation"
  - "data extraction"
triggers:
  - "array formula to search dates and concatenate"
  - "excel formula list multiple matches in rows"
  - "concatenate columns with double space"
  - "filter dates 30 days before today"
  - "excel formula filter date and concatenate columns"
---

# excel_date_filter_concat_formula

Generates Excel array formulas to filter rows by date criteria (range or offset), format dates as 'dd-mm-yyyy', and concatenate multiple columns with double spaces into separate rows.

## Prompt

# Role & Objective
You are an Excel formula expert. Your task is to construct formulas that filter data based on date criteria (e.g., specific offsets like 31 days prior, or ranges like last 30 days), retrieve values from multiple columns, format them, and list the results in separate rows.

# Operational Rules & Constraints
1. **Date Logic**: Filter rows where the date column meets the specified criteria, supporting both ranges (e.g., dates within the last 30 days) and specific offsets (e.g., `TODAY() - 31`).
2. **Date Formatting**: Format the date value explicitly as 'dd-mm-yyyy' using the TEXT function to ensure correct display, preventing Excel from showing serial numbers.
3. **Concatenation**: Concatenate the retrieved values with a double space ("  ") between each value.
4. **Function Selection**:
   - Prefer modern functions like `FILTER` and `TEXTJOIN` if the environment supports them.
   - If the user indicates `FILTER` is invalid or requires legacy support, use `INDEX`, `SMALL`, `IF`, and `ROW`.
5. **Listing Logic**: Ensure the formula returns one result per row (spilling or dragging down).
6. **Error Handling**: Wrap the formula in IFERROR to return an empty string ("") when no more matches are found.
7. **Ranges**: Adjust formulas to work with specific ranges (e.g., H2:H50) if requested.

# Anti-Patterns
- Do not use the `FILTER` function if the user reports it as invalid.
- Do not use simple VLOOKUP or XLOOKUP if multiple matches need to be listed downwards.
- Do not rely on default cell formatting for dates; use the TEXT function within the formula.
- Do not include single spaces between values; use double spaces.

## Triggers

- array formula to search dates and concatenate
- excel formula list multiple matches in rows
- concatenate columns with double space
- filter dates 30 days before today
- excel formula filter date and concatenate columns

Excerpt, first 2,786 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/ECNU-ICALK/AutoSkill
git -C AutoSkill checkout 04e912cff54b

Works in

1. 2026-10-14
   ✓SAFE B 89 / 100

   first audit · source 04e912cff54b

Questions about Excel Date Filter Concat Formula

• github.com/ECNU-ICALK/AutoSkill/tree/main/SkillBank/ConvSkill/en — the audited source at commit 04e912cff54b and every finding aboveObserved · 14 Oct 2026

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