Question

I have a table with many rows of data, which has an column filled with a date.
I need to select their first row and their last row between two dates.

Example:
Score table:

id      userId       value1         value2        date
1       1            1              2             2012-09-01 00:00:00
2       1            5              8             2012-09-03 00:00:00
3       1            7              11            2012-09-04 00:00:00
4       1            9              14            2012-09-05 00:00:00

I need to get the values value1 and value2 between the dates 2012-09-02 00:00:00 and 2012-09-04 00:00:00 of userId 1.

The desired result should be:

userId    value1_old    value2_old    value1_new    value2_new
1         5             8             7             11

The values _old should contain the data older then, but closest to the date 2012-09-02 00:00:00.
The values _new should contain the data earlier then, but closest to the date 2012-09-04 00:00:00

The problem is, how do I get these data? I don’t know how to get this to work.

Thanks in advance,
Mark

Answer 1

SELECT   t.userId,
         first.value1 AS value1_old,
         first.value2 AS value2_old,
          last.value1 AS value1_new,
          last.value2 AS value2_new
FROM     (
  SELECT   userId, MIN(date) AS first, MAX(date) AS last
  FROM     Score
  WHERE    userId = 1
       AND date BETWEEN '2012-09-02 00:00:00' AND '2012-09-04 00:00:00'
) t
    JOIN Score first ON first.userId = t.userId AND first.date = t.first
    JOIN Score  last ON  last.userId = t.userId AND  last.date = t.last

See it on sqlfiddle.