Cornishlight was featured as 'Site of the Month' on such a Database type Site and got one visitor a fortnight from them. Before placing an Advertisement on any web-site ask them how many people a day are likely to look at your page. In the case of most you will be surprised how few. There you may be competing with that of everyone else in your Village, Town or County. Database's assume that a person knows exactly what type of accommodation they require and in what location.
Human nature is to be flexible and to like to browse.
That is difficult with a database. The other problem with being listed on such database or phone book type sites is that people tend to enquire to several establishments so that the chances of yours getting that booking are reduced. Success stories from here in Cornwall. A hotel in Newquay with its own site, is getting hundreds of visitors a week. The Isles of Scilly Travel Company offers booking through its web-site.