I found how to use, inside a PL/pgSQL function, a two-dimensions array (matrix).
There is a limitation: the number of the 'columns' of the matrix is fixed at
declaration time (in DECLARE section) and you need to manually initialize all
the elements in the first 'row' of the matrix.
The number of rows is unlimited and can be sized at runtime.
Here is the code that can help you.
If someone know how to manage an NxN array without limitations, please replay
to this thread.
I'm using PostgreSQL 7.4.1 on RH7.3
CheersSergio
CREATE OR REPLACE FUNCTION "testarray" (integer) RETURNS SETOF integer AS'
DECLARE n alias for $1; -- number of rows is passed as argument i INTEGER; j integer; k
INTEGER:= 3; -- matrix columns number b integer[] := array[0,0,0]; -- need it to initialize the
matrix!! a integer[][] := array[[0,0,0]]; -- need it to initialize the matrix!!
begin
for i in 1..n loop -- the i loop can start obviously from 2 (the first
row is already present...) but for our purpose here we use 1 a := array_cat(a,b); for j in 1..k loop
a[i][j] := i*j; end loop; end loop; for i in 1..n loop
return next null; return next i; -- need it to format in some way the output :) return
nextnull;
for j in 1..k loop return next a[i][j]; end loop;
end loop; return;
end
'LANGUAGE 'plpgsql';
here is the output:
=> select * from testarray(8); testarray
-----------
1
1 2 3
2
2 4 6
3
3 6 9
4
4 8 12
5
5 10 15
6
6 12 18
7
7 14 21
8
8 16 24
(48 rows)
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