SQL / BROWSER UTILITY
SQL Join Calculator
Calculate join row counts and preview matching and unmatched keys.
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Your result
Choose a join, then calculate to see the matching rows.
| Left key | Right key |
|---|
Copy result data and compare all join counts
Good to know
Enter one join key per row from each table. This models an equality join with case-sensitive text keys: spaces are significant, blank lines are ignored, and duplicate rows are retained. Use the exact token \N for a SQL NULL key; NULL never equals NULL. Counts include every duplicate pairing. The table shows at most 100 pairs. NULL means an unmatched or missing key. Copyable JSON and all join counts are available in the expandable details. Database types and collations may compare keys differently. No SQL is executed.
Example: A contains 1, 2, 2; B contains 2, 2, 3. INNER returns 4 rows, LEFT and RIGHT return 5 each, FULL returns 6 and CROSS returns 9.