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.
| Is This Answer Correct ? | 3 Yes | 0 No |
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