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How to delete duplicate row from table sql

If we want to delete the duplicate row from a table we can perform it by sq l. Consider the following SQ L query


 delete from PATIENT_INFO   
 where MrNo in (select MrNo  
         from PATIENT_INFO group by MrNo  
         having (count(PatientId))>1) and   
         PatientId not in (select min(PatientId)  
              from PATIENT_INFO   
              group by MrNo  
              having (count(PatientId))>1)

Here PATIENT_INFO    is Table Name. and PatientId  is the primary key of the table. and we want to delete the duplicate MrNo  .
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