Answer Posted / vipul dalwala

For emample we have table called DUPtable.

DESCRIBE DUPtable;

+--------+-----------------+
| Field | Type |
+--------+-----------------+
| id | Auto Increament |
| field1 | varchar(20) |
| field2 | varchar(20) |
| field3 | varchar(20) |
+--------+-----------------+

And we want to delete duplicate rows from DUPtable (Same
combination of field1, field2 and field3) .

Solution:

Step 1: Create a Temporary table;

CREATE TEMPORARY TABLE tmpDUPtable
SELECT id FROM DUPtable GROUP BY field1, field2, field3;


Step 2: Delete query to remove Rows not in 'tmpDUPtable'
table.

DELETE from DUPtable WHERE id NOT IN (SELECT id FROM
tmpDUPtable);

Step 3 DROP tmpDUPtable

DROP TABLE tmpDUPtable;


I hope this will help.

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