A traditional database usually contains structured data. A query on a database limits the data depending on different conditions specified by the user. Each condition in the query is evaluated as true/false, and the rows that don't satisfy the conditions are eliminated. However, full-text search is much more complicated. The data is unstructured, or at least the queries are.
We often need to search for the same text across one or more fields. The documents can be quite large, and the query word might appear multiple times in the same document and across several documents. Displaying all the results of the search will not help as there could be hundreds, if not more, and most documents might not even be relevant to the search.
To solve this problem, all the documents that match the query are assigned a score. The score is assigned based on how relevant each document...