>>Check this new article http://social.technet.microsoft.com/wiki/contents/articles/19670.t-sql-useful-links.aspx#SQL_Server_Internals
>>
>>Go to the 3rd article in SQL Server Internals section - to the article by Paul White. It may help you.
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>This is increasing as data is populated in that field. Twice, I cleaned all the values for that field in those records. The result was instant. Then, as the robot keeps processing those tasks, the log field is being populated. As each task gets its log, the time to execute the SQL increases.
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>What we did elsewhere is to simply rely on a second field. This is a flag indicating or not if a value is in the field. If it is, I can then use that flag field instead of the log field in the query. Then, in the logic of the code, if the flag is True, I know I can enable a View column in my list to point to a page to show the log. I will apply the same technic here.
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>With those articles, compression will help but will be affected by the size. With the approach I will take, this will not be a factor. This should resolve the issue.
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>Thanks for the reference.

Did you read that article and looked at the option he suggests? I am re-reading it myself again right now.