SQL Query to concatenate column values from multiple rows in Oracle

http://stackoverflow.com/questions/4686543/sql-query-to-concatenate-column-values-from-multiple-rows-in-oracle

 

Table A

PID
A
B
C

Table B

PID   SEQ    Desc

A     1      Have
A     2      a nice
A     3      day.
B     1      Nice Work.
C     1      Yes
C     2      we can 
C     3      do 
C     4      this work!

Output of the SQL should be –

PID   Desc
A     Have a nice day.
B     Nice Work.
C     Yes we can do this work!


SELECT pid, LISTAGG(Desc, ' ') WITHIN GROUP (ORDER BY seq) AS desc
FROM   B
GROUP BY pid;

Then join to A to pick out the pids you want.