Mysql distinct search for one column

Question

I would like to use an SQL query to return from a database the first occurence of a data value (DUT's serial number). I have a database that contains the DUT serial number, the test status (i.e. pass or fail), and the date the DUT was tested. Since I am trying to determine the first pass yield for this test lot of DUTs, I want to only query the database for the first occurence (i.e. earliest date DUT was tested), and retunr the test status for this entry. Any recommendations on what type of SQL commadn I could use to get this data?
Below is an example of the database:
DUT SN         TEST STATUS             DATE TESTED
001                Failed                          6-1-2011
001                Passed                        6-2-2011
002                Passed                        6-1-2011
003                Passed                        6-1-2011
004                Failed                          6-2-2011
004                Passed                        6-2-2011
005                Passed                        6-2-2011
THis is the data I would like to extract:
DUT SN         TEST STATUS             DATE TESTED
001                Failed                          6-1-2011
002                Passed                        6-1-2011
003                Passed                        6-1-2011
004                Failed                          6-2-2011
005                Passed                        6-2-2011
As you can see I only want to get the first entry for a serial number. This first entry will be used to determine the first pass yield for the lot of boards.
Thank you in advance for your time and assistance,
Jim
Solved!
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Answer 1

I don't believe you can do one query to get what you want.  I use this query:
... and then process the results like this:
...to get first-pass yield information.
Jim
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