profiling-tables

SKILL.md

Comprehensive statistical and quality analysis of database tables with structured profiling output.

Generates column-level statistics tailored to data type: min/max/percentiles for numeric columns, length metrics for strings, date ranges for timestamps

Performs cardinality analysis to identify categorical vs. high-cardinality columns and detect skewed distributions

Assesses data quality across five dimensions: completeness (NULL rates), uniqueness (duplicates), freshness (update timestamps), validity (range/format checks), and consistency (logical contradictions)

Outputs a structured profile including schema overview, key statistics, quality scores, identified issues, and recommended follow-up queries for new team members

Data Profile

Generate a comprehensive profile of a table that a new team member could use to understand the data.

Step 1: Basic Metadata

Query column metadata:

SELECT COLUMN_NAME, DATA_TYPE, COMMENT
FROM <database>.INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = '<schema>' AND TABLE_NAME = '<table>'
ORDER BY ORDINAL_POSITION

If the table name isn't fully qualified, search INFORMATION_SCHEMA.TABLES to locate it first.

Step 2: Size and Shape