Uniqueness: Duplicate Keys, Distinct Counts & Duplicate Emails
This lesson is part of the course
In this lesson
You flag rows whose customer ID appears more than once, count distinct IDs, compute the uniqueness rate, find duplicate emails that differ only in capitals and colour the duplicate keys.
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Lessons in this course
- Completeness: Blank Cells, Field Completeness & Complete Records Locked
- Validity: Format, Allowed-Value and Range Rules Locked
- Uniqueness: Duplicate Keys, Distinct Counts & Duplicate Emails Locked
- Consistency across Tables: Orphan Keys and Conflicting Values Locked
- Timeliness: Entry Lag, SLA Compliance, p90 and Freshness Locked
- Accuracy: Checking a Sample against Verified Values Locked
- The DQ Scorecard: Weighted Scores, RAG Status & Icon Sets Locked
- DQ Trend Dashboard & the Cost of Poor Data (with a Chart) Locked