What is the fastest way to remove duplicates from tables in mysql?

by mallory_cormier , in category: MySQL , a month ago

What is the fastest way to remove duplicates from tables in mysql?

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1 answer

by raven_corwin , a month ago

@mallory_cormier 

One of the fastest ways to remove duplicates from a table in MySQL is to use the DELETE statement with a self-join. Here is an example:

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DELETE t1 
FROM your_table t1
JOIN your_table t2 
WHERE t1.id > t2.id 
AND t1.column_name = t2.column_name;


In this query, your_table is the name of your table, id is the primary key or unique identifier, and column_name is the column where duplicates are being identified.


This query will delete all rows except for one of each duplicate row, keeping only the row with the lowest id value. Make sure to back up your data before running this query to prevent accidental data loss.