Stop Lists
Stop lists are used when you
want to hide words in searches or to prevent from being indexed those
words that would otherwise bloat your full-text index and might cause
performance problems. Stop lists (also known as noise word lists or stop
word lists) are a legacy component from decades ago when disk prices
were very expensive. Back then, using stop lists could save considerable
disk space. However, with disk prices being relatively cheap, the use
of stop lists is no longer as critical as it once was. You can create
your own stop word list by expanding your database in SSMS and then
right-clicking on the Full-Text Stoplists
node and selecting New Full-Text Stoplist. You have an option of
creating your own stop list, basing it on a system stop list, creating
an empty one, or creating one based on another stop list in a different
database. Each catalog can have its own stop list, which is a frequently
demanded feature because some search consumers want to be able to
prevent some words from being indexed in one table but want those words
indexed in a different table. After you create a stop word list, you can
maintain it by right-clicking on it in the Full-Text Stoplists node and selecting Properties. Figure 1 illustrates this option.
The options are to add a stop
word, delete a stop word, delete all stop words, and clear the stop
list. After selecting the option you want, you can enter a stop word and
the language in which you want that stop word to be applied.
Keep in mind that the stop
lists are applied at query time (while searching) and index time (while
indexing). Changes made to a stop list are reflected real-time in
searches but applied only to newly indexed words. The stop words remain
in the catalog until you rebuild the catalog. It is a best practice to
rebuild your catalog as soon as you have made changes to your stop word
list. To rebuild your full-text catalog, right-click on the catalog in
SSMS and select Rebuild.
