Question

I’m creating a self-help FAQ type application and one of the requirements is that the end user has to be able to search for FAQ topics. I have three models of note, listed below with their relevant (i.e. searchable) columns:

Topic: Name, Description
Question: Name, Answer
Problem: Name, Solution

All three tables are linked to Topic via a TopicID column. The idea is to provide a single textbox where the user can enter a search query, something either as a sentence (e.g. “How do I perform X”) or a phrase (e.g. “Performing X” or “Perform X”), and provide all Topics/Questions/Problems that have any of the words they entered in either the name or description/answer/solution fields; the model will only ever have those columns searchable and I don’t have to worry about filtering out the common words like “How” and such (It would be nice but isn’t a requirement as it’s not an exact match but a fuzzy match).

For reasons outside of my control, I have to use a Stored Procedure. My question is what would be the most appropriate way to handle a search like this; I’ve seen similar questions regarding multiple columns but really there is not a variable number of columns, there are always two columns per table that are actually searchable. The issue is that the search query could, in theory, be nearly anything – a sentence, a phrase, a comma-separated list of terms (e.g. “x,y,z”), so I would have to split the search term into components (e.g. split on whitespace) and then search each pair of columns for every term? Is that reasonably easy to do in SQL Server? The alternative, a little messier, is to just pull all the data back and then split the query and filter the results in the server-side code as there shouldn’t ever be that many items entered, but I would feel a little dirty doing something like that 😉

Answer 1

Suggest creating a new Full Text Catalog, and assign the table and columns to that catalog. Ensure your catalog is being updated at the right frequency for your needs.

You can then query this catalog using the FREETEXT predicate. It sounds like you need to match on those suffixes like ‘ing’, so suggest FREETEXT over CONTAINS in this case.

You can use a variable in this search, so it’ll be easy to fit into a stored proc.

declare @token varchar(256);
select @token = 'perform';

select * from Problem
where   freetext(Name, @token)
or      freetext(Solution, @token);
--this will match 'perform' and 'performing'