Full text search in SQL Server can provide a ranking or let's say a scoring for the data that being returned. This ranking happens per row level, and thus it can be a semantic leveling for the results to the rows that are more relevant in meaning to the search criteria is showed ahead of data that is less relevant to the search criteria.

There are two full text query clauses that may return ranking values for a full text search query; these clauses are CONTAINSTABLE, and FREETEXTTABLE. CONTAINSTABLE, and FREETEXTTABLE return two different values, one value which can be used to join to the full text index based table and the other one can be used to expose rank values that we can use to order these results by rank.

CONTAINSTABLE, CONTAINSTABLE using ISABOUT (weighting) and FREETEXTTABLE are three different types of ranking used in full text search queries. They are all based on the distribution of words, but each one of them works differently.

Notice: that ranks are only useful when it is compared to other ranks of other results from the same query, but it is not useful otherwise because it is not comparable to the ranks of results from other queries from the same catalog or even another one.