Data analysisbeginner
You are a data analyst documenting a dataset so other people can use it correctly. Create a data dictionary for the table below.
Table name: [TABLE OR FILE NAME]
What one row represents (if known): [e.g. "one order line", "one user per day", OR "not sure"]
Where the data comes from: [SOURCE SYSTEM, EXPORT, API]
Who will read the dictionary: [e.g. "analysts new to the team", "business users building reports"]
Schema (column names and types):
"""
[PASTE SCHEMA, DESCRIBE OUTPUT OR HEADER ROW]
"""
Sample rows (20-50, with sensitive values masked):
"""
[PASTE SAMPLE]
"""
For each column, give a table with:
- Column name
- Plain-English definition
- Data type and format (units, date format, time zone if visible)
- Allowed values or range observed in the sample
- What a null or empty value seems to mean
- Example value
- Quality warning (mixed formats, suspicious defaults like 1970-01-01 or 0, duplicates)
- Confidence: confirmed by the sample / inferred / guess
Then:
1. State the likely grain of the table and a candidate primary key, and how to verify it.
2. List questions for the data owner, ordered by importance.
Base definitions on the column names and sample only; mark anything inferred.
Works with: ChatGPT, Claude, Gemini, Any LLM
Data analysisintermediate
You are a careful data engineer. I need to clean a CSV file before analysis.
What the data is: [SHORT DESCRIPTION, e.g. "customer sign-ups exported from our CRM"]
What I will use it for: [THE ANALYSIS OR SYSTEM IT FEEDS]
Approximate size: [ROWS AND COLUMNS]
Tool I will use: [e.g. Python with pandas, R, Excel, SQL]
Here are the header and a sample of rows (including some problem rows):
```
[PASTE HEADER + 20-50 ROWS]
```
Step 1 - Profile: for each column give the likely meaning, expected type, and problems you can see (missing values, mixed formats, inconsistent categories, outliers, duplicates, encoding issues, leading/trailing spaces).
Step 2 - Plan: a numbered cleaning plan ordered by impact. For each step say what changes, why, and how many rows it might affect.
Step 3 - Decisions for me: list choices that depend on business rules (e.g. drop or impute missing values) with your recommended default.
Step 4 - Code: write [TOOL] code that applies the plan, keeps the original file unchanged, and logs how many rows each step changed or removed.
Step 5 - Checks: list validation checks to run after cleaning.
Base your profile only on the sample; say clearly when a problem may exist in rows you have not seen.
Works with: ChatGPT, Claude, Gemini, Any LLM