add class model and some code providing by IDE
now model extend QAbstractTableModel
add sql support in .pro
change base class for model now it is QSqlTableModel
change inheritance modificator in model
convert int into Qstring in changebookdialog
declarate methods of model
add implementation functions which connect vodel with database and
disconnect it
set fixed size for dialog
add 2 querys: one create table and another add book
add new signal which generate when record must be added is invalid
and querys for add book delete it and swap another
add parenthese
change invalid driver name 'SQLITE' onto 'QSQLITE'
add comma into query
a lot of changes in internal structure of model to make it usable as
QSqlTableModel
corect sql queryes (surround string constants with '')
function now work with copys of objects( references not avaliable
because it is Qt)))