PostgreSQL 9.1 - iteration over array
I finished patch that enable iteration over array. I hope so new syntax can helps to better readability. There are a few samples from regress tests:
create or replace function fora_test()
returns int as $$
declare x int; s int = 0;
begin
for x in array array[1,2,3,4,5,6,7,8,9,10]
loop
s := s + x;
end loop;
return s;
end;
$$ language plpgsql;
select fora_test();
create or replace function subscripts(anyarray, int)
returns int[] as $$
select array(select generate_subscripts($1,$2));
$$ language sql;
create or replace function fora_test()
returns int as $$
declare x int; s int = 0;
a int[] := array[1,2,3,4,5,6,7,8,9,10];
begin
for x in array subscripts(a, 1)
loop
s := s + a[x];
end loop;
return s;
end;
$$ language plpgsql;
create or replace function fora_test()
returns int as $$
declare x record;
a fora_point[] := array[(1,2),(3,4),(5,6)];
begin
for x in array a
loop
raise notice 'point=%', x.x;
end loop;
return 0;
end;
$$ language plpgsql;
select fora_test();
create or replace function fora_test()
returns int as $$
declare x int; y int;
a fora_point[] := array[(1,2),(3,4),(5,6)];
begin
for x, y in array a
loop
raise notice 'point=%,%', x, y;
end loop;
return 0;
end;
$$ language plpgsql;


2 Comments:
very nice.
I've always wondered why iterating over array wasn't possible form the beginning. Now with Your patch it is,
Thank You.
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