sql selection

Question

i have two  tables name as Room_Table  and category table in this common column is 'id'

 

select oom_no,roomtype,tariff from category, room_table t1 where category.id= t1.id and category='"+combobox.text+"' 

when i select luxury in combobox it display roomnos are 101,102,103,104

 when i select Superluxury in combobox it display roomnos are 201,202,203,204

     after select roomno like 101 and store another tale name as Reserved

then again i want to store to another room at the time 101 is not to dispalay in combobox

     

       and  also  again i want same pattern select oom_no,roomtype,tariff from category, room_table t1 where category.id= t1.id and                                                                                                                                                                                                                                                                          category='"+combobox.text+"'