1.HOW TO DELETE DUPLICATE RECORDS FROM A TABLE?

Question

Accepted Answer

To delete duplicate records from a table, we can use the DISTINCT keyword or GROUP BY clause in SQL.

Use the DISTINCT keyword to select unique records from the table.
Use the GROUP BY clause to group the records by a specific column and select only the distinct groups.
Use the HAVING clause to filter out groups with more than one record.
Create a temporary table with distinct records and then delete the original table and rename the temporary table.
Use the ROW_NUMBER() function to assign a unique number to each record and delete the duplicates with a higher number.
Use a subquery to select the distinct records and delete the duplicates from the original table.

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