Re: Saber si el campo es PK ?

Mira yo hice un PL/PgSql para obtener el PK de una tabla, si te sirve la
puedes modificar para obtener el resto de la información.

-- descripción: regresa el nombre de los campos que forman la llave primaria
de una tabla
-- param: nombre de la tabla
create or replace function getpkey(text) returns integer as '
declare
tabla_oid integer;
real_name text;
tabla alias for $1;
exp_tabla text;
index_def text;
inicio integer;
fin integer;
tmp text;
pos integer;
campo text;
noCampos integer;

begin

noCampos :=0;
exp_tabla:=''^''||tabla||''$'';
pos:=-1;

select array_upper(conkey,1) as no from pg_catalog.pg_constraint where
conname like tabla||''%''
and contype = ''p''into noCampos;

if noCampos is null then
raise notice ''ESTA TABLA NO TIENE LLAVE PRIMARIA'';
return 0;
else
raise notice ''Numero de campos: %'',noCampos;
end if;

select c.oid FROM pg_catalog.pg_class c LEFT JOIN
pg_catalog.pg_namespace n
ON n.oid = c.relnamespace WHERE c.relname ~ exp_tabla AND
pg_catalog.pg_table_is_visible(c.oid)
into tabla_oid;

select c2.relname, pg_catalog.pg_get_indexdef(i.indexrelid, 0,
true)FROM pg_catalog.pg_class c,
pg_catalog.pg_class c2, pg_catalog.pg_index i WHERE c.oid =
tabla_oid AND c.oid =
i.indrelid AND i.indexrelid = c2.oid ORDER BY i.indisprimaryDESC,
i.indisunique DESC, c2.relname into real_name,index_def;

raise notice ''real name <--> %'',real_name;
inicio := position(''('' in index_def);
tmp := substring (index_def from inicio+1 for char_length(index_def));
fin := position('')'' in tmp);
tmp := substring (tmp from 0 for fin);

while pos!=0 loop

pos := position('','' in tmp);
if pos = 0 then
campo := substring(tmp from 0 for char_length(tmp)+1);
else
campo := substring(tmp from 0 for pos);
end if;
raise notice ''campo <--> %'',ltrim(campo);
tmp := substring(tmp from pos+1 for char_length(tmp));

end loop;

return tabla_oid;
end;
' language 'plpgsql';

--
Jc3