Question

I do some insert in a MySQL DB with a for cycle.

I have a problem with the auto-increment, ’cause after the first insert I obtain an com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException.

Here the code:

for (int i=0; i<numKeys; i++) {
try {
   stm1 = this.db_connection.prepareStatement("INSERT INTO mytable (Cod, Prop, Field, Value) VALUES (?,?,?,?)");
   stm1.setInt(1, Statement.RETURN_GENERATED_KEYS);
   stm1.setInt(2, 0);
   stm1.setString(3, aname);  
   stm1.setString(4, avalue);
       stm1.executeUpdate();
    } catch (SQLException e) {
        e.printStackTrace();
    }
}  

Cod is an auto-increment-field.

Answer 1

If it is a auto incremented field then there is no reason to pass it in as an argument, just don’t include it in the Insert statement.

stm1 = this.db_connection.prepareStatement("INSERT INTO mytable (Prop, Field, Value) VALUES (?,?,?)");

And remove the appropriate setInt method below.