Maintaining Full-Text Indexes

Dave Mason talks about full-text index maintenance:

My first encounter with full text indexes and degraded performance was related to an enhancement I made to an aspx page years ago. I wanted all of the search fields to use an AutoComplete AJAX extender to mimic the behavior you see when you type a few letters into the search field on Google.com or Bing.com. A traditional non-clustered index wasn’t sufficient for the “Location Address” field, so I settled on a full text index–it worked very well.

After some amount of time (I don’t remember how long), performance slowed considerably. I was surprised to find the full text index for “Location Address” had a large number of fragments. I wish I had kept some notes on my findings. I can’t remember how may fragments there were, but I’m thinking it was in the 15-20 range. If memory serves me, Orange Co., FL has about 400,000 physical location addresses. The underlying table had one row per location address. Knowing me, the indexed column was probably VARCHAR(100) or VARCHAR(128). This does’t seem like a huge amount of data, so I was surprised the full text searches were slow, even with 15-20 fragments. Reorganizing the related full text catalog made a world of difference. Performance improved drastically.

All indexes need maintenance.  Dave has a script to help with full-text indexes.

Related Posts

How Non-Clustered Index Key Columns Are Stored

Kendra Little walks through page-level details on a non-clustered index: Just like in the root page and the intermediate pages, the FirstName and RowID columns are present. Also in the leaf: CharCol, our included column appears! It was not in any of the other levels we inspected, because included columns only exist in the leaf of a […]

Read More

Using DMVs To Plan Out Your Indexes

Eric Blinn explains how to use two particular DMVs to see which index changes you might want to make: Missing Indexes This group of DMVs records every scan and large key lookups.  When the optimizer declares that there isn’t an index to support a query request it generally performs a scan.  When this happens a […]

Read More

Categories

March 2016
MTWTFSS
« Feb Apr »
 123456
78910111213
14151617181920
21222324252627
28293031