I need to delete duplicate record from table in mysql.
So i have a table name "employee" fields are empid, empname, empssn
for getting duplicate record i have written a query
SELECT COUNT(empssn), empssn
FROM employee
GROUP BY empssn
HAVING COUNT(empssn)>1
Now i want to delete duplicate records. for that i have written query is.
DELETE FROM employee
WHERE (empid, empssn) NOT IN (SELECT MIN(empid), empssn
FROM employee
GROUP BY empssn);
you can assume records in table are
EmpId EmpName EmpSSN
-------------------------------
1 Jack 555-55-5555
2 Joe 555-56-5555
3 Fred 555-57-5555
4 Mike 555-58-5555
5 Cathy 555-59-5555
6 Lisa 555-70-5555
7 Jack 555-55-5555
8 Mike 555-58-5555
9 Cathy 555-59-5555
10 Lisa 555-70-5555
11 Lisa 555-70-5555
but i have a mysql error is
You can't specify target table 'employee' for update in FROM clause
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