The SQL Server can be installed as case-sensitive or not (Default). In the second case any character comparisons would be case-insesitive. You can make them case sensitive by converting string values to a binary format

SELECT * FROM history 
WHERE CAST(type AS binary(1)) IN ( CAST('L' AS binary(1)))

>Hi,
>
> SELECT * FROM history WHERE type IN ('L')
>
>seems to ignore case, because I'm getting all
>records with both upper and lower case L's.
>
>Is there anyway to trap out the lower case L's?
>
>Thanks,
>
>Tom
>
>PS I tried to search for 'IN keyword', but the search
>function says I have to have three characters minimum.