How to delete duplicate data

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Accepted Answer

To delete duplicate data in SQL, use the DISTINCT keyword or GROUP BY clause.

Use the DISTINCT keyword to select unique values from a table.
Use the GROUP BY clause to group rows with the same values together and then select the unique groups.
Use the HAVING clause to filter out groups with more than one row.
Use the DELETE statement with a subquery to delete duplicate rows.
Example: SELECT DISTINCT column_name FROM table_name;
Example: SELECT column_name1, column_name2 FROM table_name GROUP BY column_name1, column_name2 HAVING COUNT(*) > 1;
Example: DELETE FROM table_name WHERE column_name IN (SELECT column_name FROM table_name GROUP BY column_name HAVING COUNT(*) > 1);

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