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Question

So let's say I have two databases, one for production purposes and another one for development purposes.

When we copied the development database, the full-text catalog did not get copied properly, so we decided to create the catalog ourselves. We matched all the tables and indexes and created the database and the search feature seems to be working okay too (but been entirely tested yet).

However, the former catalog had a lot more files in its folder than the one we manually created. Is that fine? I thought they would have exact same number of files (but the size may vary)

Answer 1

First ...when using full text search I would suggest that you don't manually try to create what the wizard does for you. I have to wonder about missing more than just some data. Why not just recreate the indexes?

Second ...I suggest that you don't use freetext feature of sql server unless you have no other choice. I used to be a big believer in freetext but was shown an example of creating a Lucene(.net) index and searching it in comparison to creating an index in SQL Server and searching it. Creating a SQL Server index in comparison to creating a Lucene index is considerably slower and hard to maintain. Searching a SQL Server index is considerably less accurate (poor results) in comparison to Lucene. Lucene is like having your own personal Google for searching data.

How? Index your data (only the data you need to search) in Lucene and include the Primary Key of the data that you are indexing for use later. Then search the index using your language and the Lucene(.net) API (many articles written on this topic). In your search results make sure you return the PK. Once you have identified the records you are interested in you can then go get the rest of the data and/or any related data based on the PK that was returned.

Gotchas? Updating the index is also much quicker and easier. However, you have to roll your own for creating the index, updating the index, and searching the index. SUPER EASY to do...but still...there are no wizards or one handed coding here! Also, the index is on the file system. If the file is open and being searched and you try to open it again for another search you will obviously have some issues...so writing some form of infrastructure around opening and reading these indexes needs to be built.

How does this help in SQL Server? You can easily wrap your Lucene search in a CLR function or proc which can be installed in the database that you can then use as though it were native to your t-SQL queries.