[HACKERS] PL/pgSQL proposal: using list of scalars in assign stmts, fore and fors stmts
Hello Now, statements EXECUTE INTO and SELECT INTO allow using list of scalars. FORe and FORs allow only ROW o RECORD VARIABLE. I'll plan and I did it enhance this stmts: for := FOR target IN {SELECT | EXECUTE} ... LOOP target := {row|record|comma separated list of scalar vars} assign := target2 ':=' expression target2 := {row|record|variable|'ROW(' comma separated list of scalar vars ')'} for example: CREATE OR REPLACE FUNCTION test(OUT _rc, OUT _x varchar, OUT _y varchar) RETURNS SETOF RECORD AS $$ DECLARE _r RECORD; BEGIN rc := 0; -- old style; FOR _r IN SELECT generate_series AS x, generateseries + 1 AS y FROM generate_series(1,4) LOOP _rc := _rc + 1; _x := _r.x; _y := _r.y; RETURN NEXT; END LOOP; -- new one FOR _x,_y IN SELECT generate_series, generateseries + 1 FROM generate_series(1,4) LOOP _rc := _rc + 1; RETURN NEXT; END LOOP; -- new two FOR _r IN SELECT generate_series AS x, generateseries + 1 AS y FROM generate_series(1,4)LOOP _rc := _rc + 1; ROW(_x,_y) := _r; RETURN NEXT; END LOOP; RETURN; END; $$ LANGUAGE plpgsql; any comments? Regards Pavel Stehule _ Najdete si svou lasku a nove pratele na Match.com. http://www.msn.cz/ ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
Re: [HACKERS] PL/pgSQL proposal: using list of scalars in assign stmts, fore and fors stmts
Pavel Stehule [EMAIL PROTECTED] writes: for := FOR target IN {SELECT | EXECUTE} ... LOOP target := {row|record|comma separated list of scalar vars} This part seems all right to me. assign := target2 ':=' expression target2 := {row|record|variable|'ROW(' comma separated list of scalar vars ')'} As I already said on -patches, I consider this a bad idea. It's too error prone (because there's no easy way of seeing what the field order will be). And it doesn't add anything that you can't do now. I think a series of var = rec.field assignments is a preferable way to do it. regards, tom lane ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
Re: [HACKERS] PL/pgSQL proposal: using list of scalars in assign stmts, fore and fors stmts
On Thu, Dec 22, 2005 at 10:18:16AM +0100, Pavel Stehule wrote: Hello Now, statements EXECUTE INTO and SELECT INTO allow using list of scalars. FORe and FORs allow only ROW o RECORD VARIABLE. I'll plan and I did it enhance this stmts: for := FOR target IN {SELECT | EXECUTE} ... LOOP target := {row|record|comma separated list of scalar vars} assign := target2 ':=' expression target2 := {row|record|variable|'ROW(' comma separated list of scalar vars ')'} How about: target2 := {row|record|variable|'[ROW](' comma separated list of scalar vars ')'} instead, where the ROW is optional? Cheers, D -- David Fetter [EMAIL PROTECTED] http://fetter.org/ phone: +1 415 235 3778 Remember to vote! ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: [HACKERS] PL/pgSQL proposal: using list of scalars in assign stmts, fore and fors stmts
David Fetter [EMAIL PROTECTED] writes: How about: target2 := {row|record|variable|'[ROW](' comma separated list of scalar vars ')'} instead, where the ROW is optional? If we're going to do this at all (which I'm still agin), I think the ROW keyword is important to minimize ambiguity. If you are allowed to start a statement with just (x, ... then there will be way too many situations where the parser gets confused by slightly bad input, resulting in way-off-base syntax error reports. Or worse, no syntax error, but a function that does something else than you expected. I know that ROW is optional in the bit of SQL syntax that this proposal is based on, but that's only because the SQL spec says we have to, not because it's a good idea. regards, tom lane ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: [HACKERS] PL/pgSQL proposal: using list of scalars in assign
Tom Lane wrote: David Fetter [EMAIL PROTECTED] writes: How about: target2 := {row|record|variable|'[ROW](' comma separated list of scalar vars ')'} instead, where the ROW is optional? If we're going to do this at all (which I'm still agin), I think the ROW keyword is important to minimize ambiguity. If you are allowed to start a statement with just (x, ... then there will be way too many situations where the parser gets confused by slightly bad input, resulting in way-off-base syntax error reports. Or worse, no syntax error, but a function that does something else than you expected. I know that ROW is optional in the bit of SQL syntax that this proposal is based on, but that's only because the SQL spec says we have to, not because it's a good idea. I see no virtue in this either. It strikes me as just more syntactic sugar, and unless I am misreading or out of date it would be another incompatibility with Oracle. I don't mind doing that, but I think it should be for a better reason than that it accords with someone's taste in syntactic style. I'd be somewhat more persuaded if Oracle did this. I also agree with Tom's comments about requiring ROW. As I observed regarding another syntax proposal, terseness is not always good, and redundancy is not always bad. cheers andrew ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq