This is not too far to my proposal - and it is fully adequate alternative.
The ANSI form is related to SET or UPDATE commands - so in this case I see classic languages style https://en.wikipedia.org/wiki/Assignment_(computer_science) better. The assign statement in PLpgSQL is not related to embedded SQL. If we introduce SQL syntax and SET commands for schema variables then ( ) syntax is perfect, but for := PLpgSQL I am not sure
It is maybe strange, but
SET (a,b) = (SELECT a,b FROM foo)
a, b := fx()
are sentences from two independent worlds and different syntax can be correct (depends how much we would to integrate procedural and SQL worlds .. 100% T-SQL, 80% SQL/PSM, ..20% PLpgSQL or 5%PL/SQL)
More thoughts:
1. syntax (a,b) := f() ... can mean - assign record to temporary composite (a,b)
2. syntax a,b := f() ... can mean - unpack result composite and assign to a, b fields
so both syntaxes has sense although we don't introduce relation to SQL - on this way
a,b := 10, 20 -- ok .. attach a=c1, b=c2
a,b := (10,20) -- ok .. attach a = r.c1, b = r.c2
(a,b) := (10,20) -- ok attach ct = rt
(a,b) := 10,20 -- ok attach ct = row(c1, c2)
@1 syntax says "create composite target", @2 syntax says "unpack result". Both should to work. Personally I prefer @1 .. due less parenthesis
Regards
Pavel
Regards
Pavel
But what, if anything, does Ada do?
What I know, no, Ada has not this statement - but the design of OUT parameters in Ada absolutely different than PostgreSQL - so in this case we cannot to use Ada language as our base :(
