Add a flag to your rooms table is_reserved
is_reserved = 0 ( room not reserved ).
is_reserved = 1 ( room is reserved ).
Then just do a query on rooms is_reserved flag and you can get a list of
rooms that are reserved and not reserved.
But as @ neuron mentioned you should also have a start and ending date fields in your reservation table.
What did you Try? What did you Get? What did you Expect?
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