数据分组

Question

I have a database that records clients who have a rating score upon entry of the service we provide, this is between 0 - 50, they are seen on average once a week and after four sessions they are re-evaluated on the same score to see a trend so say initially they may score 22 and after four weeks it may be 44 What i am after is a sql query to group this data

+----+-------+--------+
|name|initial|followup|
+----+-------+--------+
|joe |22     |        |
+----+-------+--------+
|joe |       |44      |
+----+-------+--------+

i want this to show

+----+-------+--------+
|name|initial|followup|
+----+-------+--------+
|joe |22     |44      |
+----+-------+--------+

i know this is a simple question and have done this before but tis the time of the year and the pressure is on from management many thanks in advance

Answer 1

Assuming the - means NULL , just use aggregation:

select name, max(initial) as initial, max(followup) as followup
from t
group by name;