how to locate duplicate rows in mysql code example

Example 1: find duplicates mysql column

SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;

Example 2: select where duplicate mysql

SELECT 
    col1, COUNT(col1),
    col2, COUNT(col2)
FROM
    table_name
GROUP BY 
    col1, 
    col2
HAVING 
       (COUNT(col1) > 1) AND 
       (COUNT(col2) > 1);

Example 3: mysql get latest duplicate rows

SELECT
   t1.primary_id,
   t1.duplicate_id,
   t1.data1,
   t1.data2
FROM
   table_name t1
LEFT JOIN table_name t2
	ON (t1.duplicate_id = t2.duplicate_id AND t1.primary_id < t2.primary_id) 
WHERE
	t2.primary_id IS NULL

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