How to verify in mysql if the number of rented books is lass 1

Question

Hi to everyone!
i have a book database,client db and rent db.In thje book db i have the number of each book! Clients came and rent books. I have to verify that the number of books in the table is >=1!How can I do this?
Can you please help me!
Thanks!

Answer 1

Completely untested, but should point you in the right general direction...
     // Connect to database.
     Connection C = DriverManager.getConnection("jdbc:mysql://host/database_name","username","password");
     // Prepare SQL statement to select details of requested book (by book_id?).
     PreparedStatement PStmt = C.prepareStatement("SELECT book_id, book_name, book_count FROM books where book_id=?");
     // Requested book id...:)
     int requestedBookId = 20;
     // Set placeholder value for book id.     
     PStmt.setInt(1, requestedBookId);
     // Execute...           
     ResultSet RS = PStmt.executeQuery();
     // Get record...
     RS.first();
     // Is the current book count greater than 0...     
     if ( RS.getInt("book_count") > 0 )
          // Do whatever with the "client" and "rent" databases
          // (did you mean "client" and "rent" tables?)
     // Close all     
     PStmt.close();
     RS.close();
     C.close();