The Application: The Database Module

%% @doc Create the database table required for the bookstore
setup() ->
    run_query(setup_table_books, []).
%% @doc Delete the database table required for the bookstore
teardown() ->
    run_query(teardown_table_books, []).
%% @doc Add a new book to the inventory, with no copies of it.
add_book(ISBN, Title, Author) ->
    add_book(ISBN, Title, Author, 0, 0).
%% @doc Add a new book to the inventory, with a pre-set number of owned 
%% and available copies.
add_book(ISBN, Title, Author, Owned, Avail) ->
BinTitle = iolist_to_binary(Title),
BinAuthor = iolist_to_binary(Author),
case run_query(add_book, [ISBN, BinTitle, BinAuthor, Owned, Avail) of
        {{insert,0,1},[]} -> ok;
        {error, Reason} -> {error, Reason};
        Other -> {error, Other}
end.
%% @doc Add a copy of a book to the bookstore's inventory
add_copy(ISBN) ->
    handle_single_update(run_query(add_copy, [ISBN])).
%% @doc Borrow a copy of a book; reduces the count of available 
%% copies by one. Who borrowed the book is not tracked at this 
%% moment and is left as an exercise to the reader. 
borrow_copy(ISBN) ->
    handle_single_update(run_query(borrow_copy, [ISBN])).
%% @doc Return a book copy, making it available again.
return_copy(ISBN) ->
    handle_single_update(run_query(return_copy, [ISBN])).
%% @doc Search all books written by a given author. The matching is loose 
%% and so searching for `Hawk' will return copies of books written
%% by `Stephen Hawking' (if such copies are in the system) 
find_book_by_author(Author) ->
    handle_select(
        run_query(find_by_author, [iolist_to_binary(["%",Author,"%"])])
    ).
%% @doc Find books under a given ISBN.
find_book_by_isbn(ISBN) ->
    handle_select(run_query(find_by_isbn, [ISBN])).
%% @doc Find books with a given title. The matching us loose and searching 
%% for `Test' may return `PropEr Testing'.
find_book_by_title(Title) ->
    handle_select(
        run_query(find_by_title, [iolist_to_binary(["%",Title,"%"])])
    ).