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Date: Tue, 24 Apr 2012 22:01:31 +0200
From: Andreas <maps.on@gmx.net>
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To: pgsql-sql@postgresql.org
Subject: generic crosstab ?
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Hi,

is there a generic solution to dump the result of a query as a crosstab, 
when I can't know how many columns I will need?

E.g. I get something like this:

id, x
1,  a
1,  b
1,  c
2,  l
2,  m


and I'd like to see it as:

id,  x1,  x2,  x3,  .....  xn
1,   a,   b,   c,    null, .... null
2,   l,    m,  ....

I fear the problem is I dont know n.