Question

I have a requirement where i have two records with same value except the PK. how can i delete one of them.I have plenty of such duplicate records.

Answer 1

One solution is to write a procedure that opens a cursor to a query ordered by the columns that define duplicates, and use DELETE ... WHERE CURRENT OF CURSOR when the row is a duplicate of the previous row. Here’s pseudocode for what I mean:

sql [ctx] C1 = { SELECT * FROM MyTable ORDER BY dup_column };

sql {  FETCH C1 INTO row  };
while ( !C1.endFetch() )  {
    if ( row.dup_column = prevrow.dup_column ) {
        sql [ctx] { DELETE FROM MyTable
                     WHERE CURRENT OF C1  };
    }

    prevrow.dup_column = row.dup_column;

    sql { FETCH C1 INTO ...     };
}
C1.close();