Any search on a text field will result in the table scan unless Full-Text search is used with appropriate conditions.

>Is there any performance concerns when issuing the following query on a text field in a SQL Server table?
>
>SELECT * FROM mytable where myfield LIKE '%mykeyword%'
>or
>SELECT * FROM mytable where myfield LIKE '%key1%' or myfield LIKE '%key2%'
>
>I would like to give my users keyword search lookups and I am trying to find the best possible solution.
>
>