I have the following insertion code for a person table having fields( name,ipaddress ). Both are defined as type varchar.

Qt Code: 
  1. QString personTableQstr = 
  2.             "create table Person (name varchar(40) primary key,ipaddress varchar(40))";
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I am trying to insert some entries into this table using the following code -

Qt Code: 
  1. QSqlQuery nameQuery;
  2.     nameQuery.prepare( "SELECT * FROM Person WHERE name=:name" );
  3.     nameQuery.bindValue( ":name",tempname1 ); 
  4.     nameQuery.exec();
  5.     if( !nameQuery.first() )
  6.         {
  7.  
  8.             logfile.write( QString("DB does not contain this name ...").toAscii());
  9.             QSqlQuery insertionQuery;
  10.             insertionQuery.prepare( "INSERT INTO person (name, ipaddress) "
  11.                                     "VALUES (?, ?)");
  12.             insertionQuery.bindValue(0, tempname1);   //tempname1 contains name
  13.             insertionQuery.bindValue(1, tempname2);   //tempname2 contains ip address
  14.  
  15.             if( !insertionQuery.exec() )
  16.                 {
  17.                     logfile.write( QString("\n\nInsertion of new person record failed").toAscii());
  18.                 }
  19.         }
  20. else
  21. {
  22.     logfile.write( QString("\n\nName already present in DB").toAscii());
  23.  
  24. }
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I am testing this code by inserting same value ( for name & ipaddress ) twice.Basically the first time I am trying to insert it enters the if-case. But even the second time it enters the if-case, but insertion fails & prints out "
Insertion of new person record failed
". But logically the first() API of QSqlQuery should return true for the second time insertion.

Is my assumption correct ? How does this API work ?