How do I tell if a row exists in a table?

Question

For example:

select name from person where id=2;

I wand to know if this row exists, and depending on its existence perform a certain task. I wan to do this using jdbc.

Answer 1

Use PreparedStatement to invoke this select query,

After the successful execution of query you would have instance of ResultSet returned, you could check by invoking next() if it returns true it means there was a row selected

if(resultSet.next()){
   //yes exist
}

Answer 2

The is no hasNext() method in ResultSet. The next() method moves the cursor to the next row and if there is a row then it returns true.

if(resultSet.next()){
  //do something

}
else{
  //no next row found

}